- View All Suspension
- Chassis Braces
- Suspension Arms
- Shocks and Springs
- Aero Parts
- Tech & FAQ
|Q||TRACK-SERIES coil-over update|
|A||Please keep this in mind for track series coil-over replacement orders: The following car models in Track series were changed from M12 front shock top pin to M14 front shock top pin starting October 2011. MR-CDK-NS13TS MR-CDK-NS14TS MR-CDK-SI02TS MR-CDK-MRX86TS MR-CDK-AR02TS MR-CDK-MLE03TS MR-CDK-MLE08XTS|
|Q||Can I use shorter springs on my coil-overs?|
|A||There is only 1 valid reason to ask for shorter springs-- your lower bracket is not yet physically maxed out AND the three locking spring perches are locked up against each other. A shorter spring would create more space between the top two and the third spring perch, therefore giving more height adjustment to go even lower.|
|Q||Are my struts/shocks blown? Can they be rebuilt? Revalved?|
My coil-overs are blown, can they be replaced? Can they be rebuilt? Can they be revalved?
Here at Megan Racing, we know that shocks are a wear and tear item. But do you? As a customer, a potential owner (or if you already are an owner) of a Megan Racing coil-over damper kit, whether it be the EZ STREET SERIES, STREET SERIES, TRACK SERIES, STREET-LP SERIES, EURO SERIES or SPEC-RS line up, you should already know that one of the main benefits of a coil-over assembly is that the pieces can each be individually replaced. Didn't already know that? Well now you do!
Do you remember when you first busted out your keys because a knife or box-cutter was too far away from the package and you did not want to let your new coil-over damper kit out of your sight? Seems like it was just yesterday, wasn't it? No worries, we have all been there-- and who can resist receiving new things with excitement when you spent your hard-earned (hopefully) money?! The fruits of your labor. Most of the time, these coil-overs arrive on the door step, and sometimes to an open garage awaiting their arrival, and often times they touch nothing else in this world between the cardboard they are packaged in, to the shock towers and control arms of their respective vehicles, of which they will be controlling the suspension oscillations that are thrown at the vehicle from the ridiculously rough roads you will drive your car through, the speed bumps you may at times completely ignore, or the cracks and dips on the race track that you wish you could avoid, but clip anyway, just to try to shave off those extra tenths of a second from your lap time.
Regardless of the intended purpose of your vehicle, the struts and shocks are wear and tear items and will wear out. Do not expect them to last you the life of the vehicle unless you never drive the car and when you do, it is on 100% perfectly flat roads (never going to happen). In fact, a shock absorber loses its efficiency after 50-60k miles on them, on average-- regardless of if we are talking about an OEM strut/shock or aftermarket. With that said, the question of replacement, revalving, and rebuilding often comes up-- it is a very valid question, afterall.
So, with that said, struts and shocks are indeed wear and tear items. In fact, even OEM suspension has a limited life-span. Typically, their performance deteriorates as soon as 50-60k miles of use simply from the road qualities we experience stateside. A majority of people do not change the shocks/struts despite this, but for an aftermarket coil-over setup where the springs are generally much stiffer than the original spring rates, a blown strut or shock would be that much more evident because the stronger struts/shocks on these aftermarket coil-overs do much more work than the original struts/shocks simply because they are utilized with heavier spring rates.
Let us first take a look at a typical coil-over assembly:
First of all, this particular coil-over assembly is a front passenger coil-over from a Honda Civic 2001-2005 EM2, part number MR-CDK-HC01. Notice that each individual component can be disassembled, even down to the upper and lower bearings that go around the pillow ball mount. Each and every piece can be purchased separately should the need arise-- from the lower bracket to the top 17mm nut or the damper adjustment knob.*
*Please refer to this link for more information about the damper force adjustment knob:
With that said, even the strut or shock (depending on your application) can be replaced. Each strut or shock is available for purchase for replacement, but as always is limited to available inventory. Please check with us regarding availability.
Unfortunately, we do not offer revalve services, however the possibility of having them revalved by a third party race shop is not out of the question. Usually if you are looking for a revalve, then you would know to source a race shop specifically with this type of experience anyway. We've been notified that most Bilstein shim stacks can work with our internal components of our struts and shocks and fortunately most race shops that deal with revalving suspension will have these components, as well as fresh shock oil, available. For custom revalves, this would be you ideal solution.
We often get requests from customers asking for help in diagnosing their coil-overs and what needs to be done. Online diagnosis is very difficult so pictures may often speak louder than written text. Depending on the parties involved, of course, but this can be done and we are here to help answer any questions you may have about your suspension. Just make sure to clean them well, as you should regardless to maintain their integrity, before sending photos. For example, if you suspect a leaky shock, it is very easily distinguishable of the leak and where it arose from if the suspension area is generally clean. However if your coil-overs look very grimy, we cannot pin point where the leak came from as there are many components within the wheel well area that can contribute to that issue.
Here are typical pricing for the replacement parts typically requested:
1) Struts/shock cartridges (bare-bones, cylinder body and piston) are $135 + s/t. Exceptions include Spec RS replacements, which have their own pricing brackets. Please contact us for more information.
2) Linear-rate, 62mm inner diameter Springs are sold in pairs at $115 + s/t. Please check our application list for spring specification availability.
3) Replacement pillow ball upper mounts are priced at $65 + s/t a piece. Please be sure to check the condition of the upper and lower pillow ball bearings as well, checking for wear which usually results in metal shavings if the top nut is not properly tightened and then neglected. The upper and lower pillow ball bearings are $10 +s/t a piece.
4) Lower brackets, front or rear, steel (for McPherson struts) or aluminum, are $75 + s/t a piece. $150 for spindle models
5) Top mounts, aka upper mounts, aka top hats are $95 + s/t each.
6) Replacement locking rings and spring seats are $15 + s/t each.
7) Bumpstops, which are 35mm in length and are available in polyurethane material or varying sizes in rubber bumpstops-- please contact us to check inventory-- are priced at $20 + s/t.
8) Dust boots (please specify if it is for a McPherson strut or not) are $15 + s/t.
9) All other miscellaneous replacement parts are priced around $5-$20 whether it be the ABS plastic rings/isolators*, replacement studs for the top hats or the nuts, the 17mm top locking nut (be it integrated with the upper bearing or the nylon lock nuts), or the damper adjustor knobs.
10) A complete corner, a full coilover from the lower bracket to the top hat, may be special ordered as well. These have a 2-3 month wait as it is a special order item, downpayment may be required as per sales department.
Complete Corner Pricing:
Street- $300 ($375 if spindle model)
Track- $325 ($400 if spindle model)
Hi-Low Kits: $75
Endlinks: $55 (per pair)
Top Hat stud and nut. Always sold together. $5
Koyo Bearing/ Upper Spring Seat: $55
Top Nut: $5
Lower Pillow Ball Bearing: $5
Spanner Wrench set: $45
Brake Line Brackets (each): $25
Spring Seat Isolator (each): $5
Top Plate (Plate Only): $35
More information on the adjustable damper knobs can be found here:
*NOTE: All ABS plastic isolators/noise prevention cushions as of 2012-2013 include an inner lip to ensure proper spring seating within the upper spring seat. If isolator is flat without a lip, your upper spring seat is out-dated and you will need to purchase new ones should you choose to replace the isolator. When replacing these particular components, please inspect the components of your coilover assembly-- it is your responsibility to inquire about the details of your components. [2013/04/10]
Please contact our sales department for all purchase inquiries.
NOTE: All replacement items are subject to availability, please check availability with your Megan Racing Sales Associate to check when making the purchase inquiry. Inquiries by telephone highly recommended.
|Q||What are Roll Center Adjusters?|
Now that we are fully aware of the suspension handling benefits of adding roll center adjustoes to your lowered vehicle, there are a few caveats to make note of that will determine the correct type of roll center adjuster for your particular application.
A few notes about roll center adjusters that are particularly important to consider when choosing roll center adjusters for your vehicle. The "roll center" and "instantaneous center" are determined by lines drawn through the suspension pick up points. These "pick up points" are determined by the pivot point in the suspension layout. For example, for McPherson strut suspensions, where camber plates are utilized most of the time, the pillow ball mount where the top of the strut would pivot would be the top pick up point, and the lower pick up point would be the pivot point down below.
It is critical to take note of where the original pivot point is in the original ball-joint before purchasing the aftermarket roll center adjusters. There are certain differences between aftermarket roll center adjusters that determine if they actually make a difference, or if they are only lowering the angle of the lower control arm-- which visually does make a change, but if it changes the roll center or not would be an entirely different story.
Take a look at this picture and notice two different kinds of roll center adjusters where the pivot point (the actual ball joint) is relocated and spaced out or if the ball joint remains in the original location and the stud is actually lengthened:
This is not to say V.1 or V.2 is necessarily wrong, it entirely depends on the application. Some applications have the stud pointed down towards the ground and in other applications, the stud is pointed upwards. This is critical in determining the proper roll center adjuster for your application.
Take note of the McPherson strut layout on this following photo of a DC5:
Notice that the pivot point is effectively lowered by spacing down the ball joint-- the stud is not lengthened, though the portion of the ball joint that is pressed into the knuckle is spaced out to lower the pivot point/ball joint to effectively adjust the roll center height by lowering the pivot point.
In other words, when the stud of the ball joint is facing downward like in the above photo, the ball joint itself needs to be spaced out, to bring the pivot point lower to correct roll center. If the stud of the ball joint is pointed upwards, such is the case with the Nissan 240SX application, the stud portion of the ball joint needs to be elongated to bring the pivot point lower to effectively bring the pivot point lower to correct roll center.
It is imperatively critical to distinguish these differences before making your order for roll center adjustors, as using the correct style of roll center adjusters would determine the effectiveness of your new modification.
Furthermore, if the above photos still leave you confused and in the dark about what exactly these roll center adjusters can do for your handling, here is an explanation from an old R/C website:
|Q||Megan Racing: Coil-over Shock Dyno Plots|
Megan Racing: Coil-over Shock Dyno Plots
Shock Dynos can give plenty of information about the damper characteristics of each shock. It can give information about the spring rate capabilities, the amount of compression rebound settings with each click, an idea of the low speed and high speed characteristics of the shock.
In each item description for each coil-over application, the valving codes are listed as well as the dimensional specifications of the included shocks for each application. Below are the shock dynos for these specific valving codes. Please check with the item description for your application for specific details.
If you have any questions regarding how to read these shock dynos, feel free to contact us and our sales team and/or tech support department will be happy to help clarify anything for you.
- Basic alignment correction at lowered ride heights
- Toe correction - Re-setting toe after the vehicle is lowered is critical in maintaining tire life and often times can be tuned to alter the handling of the vehicle. For more information, please check out our article about alignments under our TECH section.
- Camber correction - Equally important as toe correction, camber settings must also be set for the priorities of the vehicle's application. Tire wear is affected as well as vehicle handling dynamics when camber settings are altered from the original factory settings.
- Why you want to adjust camber and toe - These are the basic aspects to look into when considering any changes to your current alignment setup. These are critical to tire life as well as vehicular dynamics on the road course.
- Drift/Grip settings - Often times, vehicle setup are typically different for these two differnet types of motorsports. However, when looking at the overall picture and overal alignment settings of both cars from both practices, they show a general similarity. Ultimately, these alignment settings are determined by the grip the tires provide, which makes sense that in the general sense, alignment settings for these different avenues show some similarity.
- How to set your alignment settings - In short, the way to determine how to setup your alignment is by listening to your tires. To do this, you must collect data, whether in the form of tire pressures and tire temperature data collected and/or from driver input as to how the vehicle is handling. Ultimately, the purpose of changing the alignment settings is to maximize the use of the available grip of the rubber on all four corners.
- Effects of lowered ride heights on suspension geometry
- Bumpsteer Tendencies - Often times, the tie rod arms tend to angle upwards when the vehicle's ride height is lowered significantly compared to the original static ride heights. The tie rod arms travel in their own arc, and the pivot point is the inner mounting point. Since the inner mounting point is affixed to the chassis, this lowers with the ride height. However, the outer tie rod end is connected to the hub, which in relation to the ground, does not change in height. As a result from a lowered ride height, the inner point is further down, closer to the ground, and the steering arms are pointed upwards. Because of this, and the fact that the steering arms move along their arc, a phenomenon known as bumpsteer tends to arrise as a result of lowered ride heights. Visualizing the toe change will help understand that as the suspension compresses from going over a bump, the tie rod arm moves upwards and pulls the knuckle inwards, affecting the toe setting at speed. Often times, this results in "bumpsteer" which feels like the bump pitches the car in a different direction than straight ahead. This can be a dangerous situation, especially if it occurs in a corner, and can lead to a very unpredictable handling vehicle. Look for our bump steer kits to lower the outer mounting point to make the tie rod arms more parallel to the ground to help solve the bumpsteer issues.
- Roll Couple - The front roll couple is the vehicle's tendency to roll on both the front and rear end, which ultimately determines how the vehicle handles, whether it is more oversteer prone or understeer prone. Typically the roll couple is influenced by springs, sway and damper characteristics. Altering of the suspension pick up points can also alter this aspect, however is not normally done due to financial cost.
- Roll Center on McPherson Strut Suspension Designs - Roll Center is the tendency for the car to pitch or roll in a corner. In McPherson Strut Suspension designs, it is important for the roll center to remain above the level of the ground, or else the tendency to roll over, regardless of how stiff of spring rates are being utilized, will increase. This is determined by the pick up points of the lower control arm (mainly, among other things). Roll Center Adjusters are known to effectively bring down the pivot point on the outer end, lowering the outside of the lower control arm to bring the roll center back up to managable heights. This, as well as other topics discussed in this article, are considered advanced suspension tuning techniques.
Megan Racing Products:
- Camber Kit - Often times when the suspension of a vehicle is altered with a change to the spring and shock setup, or an upgrade to a full coil-over kit, the suspension geometry determines the corresponding camber angle at the reduced static ride heights. Depending on application, there may be sufficient adjustment left within the suspension to correct any additional, unwarranted camber-- however in certain applications, camber correction is not possible without the replacement of the appropriate suspension arm with an adjustable arm to correct suspension geometry and bring camber to more desirable levels. Often times, camber kits are merely shorter, adjustable versions of the original arms they replace. With the addition of a camber kit, regardless of if both arms are pre-set to equal lengths prior to install, a full four-wheel alignment is still recommended.
- Rear Lower Control Arms - Rear Lower Control arms are mainly a weight reducing piece and would help reduce unsprung weight. Replacing the original rear lower control arms with arms of lighter material reduces unsprung weight and will improve suspension performance.
- Rear Toe Control Arms - Much like camber kits are often necessary when lowering a vehicle, toe adjustment becomes sacrificed as well-- thereby necessitating the requirement of adjustable rear toe control arms to bring toe settings back to favorable numbers.
- Rear Trailing Arms - These trailing arms allow the adjustment of Caster in the rear wheels which can drastically effect the responsiveness of the car during hard cornering or drifting. The Pillow ball ends replace the OEM soft-rubber bushings which absorb too much energy that is then wasted... the result is a more direct feel with no energy lost in the suspension system.
- Rear Traction Rods - Rear Traction Rod allows adjustment of the rear multi-link suspension. It can be adjusted to eliminate bump steer and alter other rear suspension traction settings to improve suspension response. Pillow ball unit also eliminates the flex found in factory rubber bushing allowing a tighter suspension feel and increased grip. Rear Traction Rod improves traction and is fully adjustable for your racing needs. It comes with high quality spherical bearings or hard race bushings. Prevents wheel hop for better traction and alignment changes. For race use only.
- Rear Lower Rear Arms - These rear Lower-Rear Arms are adjustable to fine tune your cars handling in the rear. When lowering a car, these will eliminate premature tire wear caused by the rear wheels riding upon the inside tread only. However, you will also slightly effect Toe and your track width of the vehicle.
- Rear Adjustable Toe Control Arms - These Toe-Control arms allow for fine-tuned adjustments to the rear toe in/out setting of the vehicle. Toe is crucial for the straight line stability and behavior of a car and is said to have more of an effect than the front toe. A little bit of toe-out in the rear will allow the car to turn easier which can reduce the tendency of initial under steer which most FWD cars are plagued with. A little bit of toe-in on the rear will give the car straight-line stability which most city drivers prefer.
- Rear Trailing Arm Bushings - These Hard Rubber bushings take the place of the OEM Soft Rubber bushing that attaches the trailing arm to the chassis. This offers a more stable and direct feeling during cornering and at higher speeds. The Hard Rubber bushing does not require maintenance or lubrication and performs with little or no noise.
- Anti-Bumpsteer Kit - Bump steer is one of the fragile points for suspension tuning on S2000. Megan Racing has created these spacers to eliminate some of the front bump steer that is created by lowering your vehicle. All the hardware are included.
- Reinforced Engine and Tranny Mounts - Through the years the soft rubber bushings deteriorate after constant flexing and vibration as well as being punished through weathering; this can cause them to tear and may seriously damage your engine and transmission. Megan Racing has developed a Hard-Rubber/Polyurethane motor mounts for the S2000.
- TPV Steering Bushing - Megan Racing has recently developed a line of reinforced bushings and are now available for the S2000 chassis. These Polyurethane Steering Bushings are designed to drastically reduce flexing in the steering line; this will improve steering feedback, drifting transitions and offer a more direct feel on any type of performance driving.
- Rear Driveshaft Spacer - The axle shaft of the Honda S2000 is design at a stock height. When the vehicle is lowered on springs, or coil over systems the axles are stretched causing some faster wear and tear on the ball joints. Megan Racing have created these spacers to bring back the stock length causing the axle to reached the stock length when the car is lowered.
- Adjustable Tie Rod Ends - These adjustable Tie-Rod ends offer a higher angle of deviation which gives slightly more steering angle and more predictability when nearing steering-lock. The 15mm of bump-steer adjustment allows the tuner to keep the control arm and tie rod at similar angles to keep a more predictable steering characteristic in this already touchy car. This allows the driver to get a more direct feel for the car and a more predictable reaction which gives the driver more confidence.
- Rear Adjustable Traction Arm - These Traction rods also allow for fine-tuned adjustments to the rear suspension geometry. By changing the length of the traction rod you change the position and pitch of which the suspension rotates upon and you change the amount of "Anti-Squat" of the rear. Although the adjustment is minimal, it can change the behavior or the vehicle during weight transfer.
- Rear Lower Trailing Arms - These trailing arms allow the adjustment of Caster in the rear wheels which can drastically effect the responsiveness of the car during hard cornering or drifting. The Pillowball ends replace the OEM soft-rubber bushings which absorb too much energy that is then wasted... the result is a more direct feel with no energy lost in the suspension system.
- Rear Lateral Arms - These rear Lower-Rear Arms are adjustable to fine tune your cars handling in the rear. When lowering a car, these will eliminate premature tire wear caused by the rear wheels riding upon the inside tread only. However, you will also slightly effect Toe and your track width of the vehicle.
- Front Roll Center Adjuster - These Roll-Center adapters are installed to correct suspension geometry after a car has been lowered. The uneven length of suspension arms causes Toe adjustments to occur drastically during braking suspension "squat", these Roll-Center Adjusters make up for the travel in the suspension arms to return suspension geometry to it's correct starting point. This allows alignment and steering to remain more consistent and predictable during aggressive driving and competition.
|Q||CDK: Are Megan Racing coil-overs maintenance free?|
|A||For the most part, coil-over damper kits that are properly installed should only need minimal maintenance. However, they definitely are not maintenance-free. Assuming the proper installation methods are used during the installation process, they do not need much maintenance. However, we recommend keeping them clean from debris to avoid corrosion that may occur between the threaded shock body, the spring perches, and the lower bracket. Also, prior to making height adjustments which involve rotating the locking spring perches and lower bracket along the length of the shock body, it is imperative that the threads are brushed free of debris that may cause damage to the threading of the shock body and respective components. The lower brackets are either made of aluminum or steel depending on the application and suspension design. For example, McPherson strut setups utilize steel lower brackets to mount to the hub/knuckle for strength, while the lower brackets for double wishbone suspension layouts are typically aluminum for less unsprung weight. Regardless of whether the lower brackets are aluminum or steel, they can still be susceptible to rust, especially in colder, humid climates, due to the shock body being made of steel. The black coating around the perimeter of the shock body protects the shock from rust and oxidation. Seized up coil-over bodies and respective components that may have seized up due to corrosion are not valid for warranty replacements. They need to be cleaned and regularly checked to assure the components of the coil-over are tight. Please refer to our other FAQ sections under the "TECH" section for addressing suspension noises.|
|Q||CDK: Damper Force Adjustment Knob Information|
Here is a photo of the damper force adjustment knob. It is usually located at the top of the coil-over assembly as it is threaded onto the very top of the shock shaft.
The black portion of the knob is what is twisted to adjust the damper force of the shock. As labeled on the knob, rotating the knob clockwise (CW) will increase the stiffness of the compression and rebound settings of the shock and rotating the knob counter-clockwise (CCW) will decrease the stiffness of the compression and rebound settings of the shock. On our Spec-RS coil-over line-up, which features separate compression and rebound adjustments, the comprssion adjustment knob is located on the external reservoir while the rebound adjustment knob is located on the main cylinder body.
To remove the damper force adjustment knob, for example to tighten the 17mm bolt, the chrome piece of the knob needs to be rotated CCW (counter-clockwise) to loosen the knob from the threads of the shock shaft. In the photo below, the chrome piece that needs to be rotated is pointed out in green:
Once the damper force adjustment knob is removed you will notice red grease on the tip of the hexagonal adjustment rod. When re-installing the damper force adjustment knob, please re-apply grease. The recommended grease to use is a petroleum based grease such as Valvoline (C) Multi-purpose Grease #614. The lack of grease may cause the surfaces within the shock shaft to corrode.
The photograph below shows some information about the damper force adjustment knobs used for Megan Racing coil-over damper kits. The part of the knob labeled "bolt" threads onto the very tip of the shock shaft, and the top part of the knob is what is used to adjust the damper force.
NOTE: When ordering replacement damper force adjustment knobs, you must measure the length of the "hexagonal adjusting rod" prior to ordering a replacement as they are not the same through the coil-over line up. Over the years, we have used different length knobs, but at this time we only produce and separately sell the knob as measured on the left in the photo below. Please meaure the opposite side knob to find out the proper length you need and if the current knobs we produce apply. In the photo below, we only produce the left side measurement now so if your knob needed is much longer, you will need replacement struts as well to use our newer knobs.
The length of a standard damper adjustment knob is 1 5/16" (hex rod including grip length) or 13/16" (hex rod length only).
|Q||CDK: Parts of a coil-over assembly|
A diagram of the typical parts of a coil-over assembly. Specific pieces such as the lower brackets and mounting plates are vehicle-specific, but the photo shows the general assembly of a coil-over unit. The following photograph displayed is vehicle specific to a 2002-2005 Honda Civic EP3 Si, which uses a McPherson strut design for the front coil-overs and a double wishbone/rear trailing arm design in the rear. The McPherson strut design allows for the use of the "camber plate" for camber adjustability on the front coil-overs, as well as the arm extending from the lower bracket for the steering tie rod arm.
Every coil-over kit is vehicle-specific, but the above photo shows the general breakdown to give you a clearer idea of simply the coil-over assemblies really are. Typically, the lower brackets as well as the top mounts differ from vehicle-to-vehicle. For example, non-strut suspension layouts do not utilize a camber plate. On double-wishbone suspensions, camber is adjusted through the use of camber kits that replace the upper, or sometimes lower, control arms. Photo above is for reference only to show the customer the hardware order when re-assembling a coil-over kit.
The below is a photograph of a fully disassembled coil-over, with the correct parts order of disassembly. The coil-over is from a 2001-2005 Honda Civic which utilizes a McPherson strut suspension layout, which is why it uses a camber plate and the specific lower bracket with the arm extended out for the steering tie rod arm.
The first item is the top 17mm nut, in this case the upper pillow-ball bearing is integrated with the 17mm nut. The 17mm nut is threaded onto the very top of the shock shaft. Immediately after the upper pillow-ball bearing/17mm nut is the upper pillow-ball assembly itself, which in this case is integrated with the upper camber plate. On non-Strut applications, the pillow-ball mount is integrated into the top mount. Right underneath the top mount or camber plate (vehicle/application dependent) is the lower pillow-ball bearing which is on top of the upper spring seat. Between the spring seat and the actual spring itself is the spring isolator, also known as the "noise prevention cushion" in the first photo of this article. There are two spring isolators which reside between the spring and the upper and lower spring perch. The two red perches lock against each other on the threaded portion of the shock body to lock the spring in place. Below these two red perches would be the third perch that locks the lower bracket into place along the threaded shock body.
NOTE: Remember to torque the top 17mm nut at the top of all McPherson struts to 40-60ft/lbs with properly calibrated torque wrench. Improper torque specification can cause the assembly to come loose and cause symptomatic clunking noise, or may damage the threads on the shock shaft when overtorqued. The "crash bolts/eccentric bolts" holding the lower steel bracket onto the knuckle also needs specific torque specs. You will need to follow the OEM torque specifications for these bolts. Your local dealership should have these torque specifications for your particular vehicle. Torque specifications for these bolts are critical to the safe operation of your coil-overs on you vehicle. We recommend you double check these torque specs with the vehicle manufacturer. Please replace the bolts with brand new OEM hardware once torqued down to specification. Due to the nature of these bolts and the excessive loads it experiences, these bolts will stretch after repeated use, rendering the possibility of hardware failure. These are one-time-use only bolts. Failure to do so will void certain warranty applicability.
Below is a photo of all of the components of the coil-over assembly put back together into one piece. This unit is basically ready to be installed on the vehicle, after all parts have been completely tightened.
|Q||CDK: Why do I hear noise from coilovers?|
Megan Racing has designed a minimalist coil-over design that is easy to adjust and tighten, limiting the amount of hardware that may potentially become loose over time. With only a 17mm nut at the very top of the shock shaft to maintain its torque specification aside from the 3 locking spring perches in most applications, there is nothing difficult about diagnosing noise issues with the coil-overs.
The noise that occurs from aftermarket coil-overs are more prevalent on McPherson strut suspension lay-outs since the entire strut assembly moves along with the hub/knuckle and the drive wheels, when the steering wheel is turned by the driver. All of the rotating forces that result from steering is transmitted through the coil-over assembly in a McPhersono strut lay-out, and when combined with the cornering loads on top of the rapid oscillation from bumps and dips in the road, there is no preventative maintenance to keep the shock body and spring perches from getting loose besides regular maintenance which is as simple as checking the coil-overs to make sure they are tight periodically. While it is good practice to do the same for double-wishbone suspension lay-outs, it is not necessary as double-wishbones do not turn the shock body when the steering wheel is turned.
There are two typical noises that result from coil-overs:
1) The first typical noises are commonly described as "rattling" and "clunking."
2) The second typical noise from coil-over assemblies is "coil-bind."
A) "RATTLING" AND "CLUNKING"
The rattling and clunking usually sound like metal-to-metal contact and usually is a sharper, more direct noise. This first issue is caused by loose components of the coil-over assembly. The best way to diagnose this type of noise is to make sure all of the components of the coil-over assembly are tightened.
1) First, you must understand that the entire "coil-over assembly" is built around the shock body-- the lower bracket is threaded onto the threaded shock body, and is locked in place by a single locking spring perch. On the piston shaft of the shock, there is a bumpstop and dust boot. The spring is held in place by two locking perches (locked against each other) on the shock body. Above the spring is the upper spring mount. On top of that is the pillow-ball upper mount, which has the lower and upper pillow-ball bearing surrounding it. The pillow-ball mount is usually incorporated into the top hat, which is what has the studs built in that bolts through the chassis holes. On McPerson strut applications, the pillow-ball mount is mounted onto the camber plate.
2) Now that you are aware of the miscellaneous parts of a coil-over assembly, this first noise is usually caused by either the locking perches on the shock body being loose, or any of the components above the spring, which is all secured in place on the shock shaft by a single 17mm nut. To access the top 17mm nut, you must remove the damper adjustment knob which is simply threaded onto the very tip of the shock shaft.
3) To tighten the 17mm nut, after the removal of the damper adjustment knob, the top of the shock shaft will be exposed. You will notice there is a 6-sided shape within the top of the piston shaft-- this is to be used for a hex tool of the appropriate size. All of our Megan Racing coil-over damper kits come with this hex tool for this very purpose (as well as to tighten the camber plate allen head bolts for strut applications). Using a closed-end wrench along with this hex tool, tighten the 17mm nut. The typical torque specification for an automotive 17mm bolt is about 40-60 lbs/in. This is a good baseline to aim for, but the critical part to take notice of is to make sure that as you are tightening the 17mm bolt, that the shock shaft is not rotating with the nut-- otherwise, the nut is not actually getting tightened. It is also a good safeguard to use an impact gun after the hex tool and wrench were used to assure that the assembly is tightened up to spec.
NOTE: Remember to torque the top 17mm nut at the top of all McPherson struts to 40-60ft/lbs with properly calibrated torque wrench. Improper torque specification can cause the assembly to come loose and cause symptomatic clunking noise, or may damage the threads on the shock shaft when overtorqued. The "crash bolts/eccentric bolts" holding the lower steel bracket onto the knuckle also needs specific torque specs. You will need to follow the OEM torque specifications for these bolts. Your local dealership should have these torque specifications for your particular vehicle. Torque specifications for these bolts are critical to the safe operation of your coil-overs on you vehicle. We recommend you double check these torque specs with the vehicle manufacturer. Please replace the bolts with brand new OEM hardware once torqued down to specification. Due to the nature of these bolts and the excessive loads it experiences, these bolts will stretch after repeated use, rendering the possibility of hardware failure. These are one-time-use only bolts. Failure to do so will void certain warranty applicability.
Coil-bind is only found on McPherson strut applications due to the nature of the strut design. Coil-bind is a "springy" noise that only occurs at low speeds while turning the wheel. Typically, coil-bind is usually experienced for example when maneuvering at slow speeds in a parking lot, where speeds are low and there are a lot of steering angle inputs. The "springy" noises is distinct from the sharper, more direct noises that occur when the assembly is loose and a component is rattling and clunking around from the miscellaneous loads stressed upon the coil-over assembly.
Many times, coil-bind is difficult to diagnose and fix-- some vehicles experience this moreso than others, and it is not a brand-specific issue. What we have suggested as a coil-bind remedy is to apply grease to the upper and lower spring isolators, also referred to as noise prevention cushions. Grease should also be applied to the lower and upper pillow-ball bearing-- this step may require disassembly of the entire coil-over unit.
The details of the coil-bind remedy are depicted in the following photo:
Customer Testimonials about their experiences with clunking coilovers:
First of all, I wrote up these articles to help users having issues with the coil-overs to have an informational section on how to diagnose issues with their vehicles. However, I often find that when they initially contact me, they refuse to believe me when I say there can only be a few areas where the coil-over can get loose-- they often assure me the shock is blown and nothing is loose. With that said, I will be adding customer experiences/feedback and how they diagnosed these issues to find that I was correct all along. Hopefully for those reading these articles in the future, the customer testimonials will help you realize that these articles are valid and that it is pointless to choose not to believe us when we tell you what the problem is with your clunking coil-overs.
1) 12/29/2010 TECH SUPPORT:
Sorry I was not able to reply to your email over the holiday. I just viewed the videos and it seems only the top nut is loose and that there is no problem with the shock. Since you said your buddy fixed it, what was the problem afterall?"
2) "at first before i called you guys i thought the bolts are loose so we checked those and they were just fine when pushing the car down the shock had a little delay so i thought it was blown then we took the strut out and found out that middle nut was loose =[" --Artem B.
3) TECH SUPPORT: "Ideally, re-greasing them is done disassembled, but I've personally been lazy when re-greasing my own suspension and I just spray it out the straw onto the top of the pillow ball mounts."
4) TECH SUPPORT: "Hello Tommy,
Here are some links from our website that may be of use to you prior to tackling the diagnosis.
http://www.meganracing.com/tech/faqs.asp?id=37&subject=Coil-overs: Why do I hear noise from coilovers?
The second link shows what is involved visually through photos, what is involved in loosening the top 17mm nut. Take a look at this second link to get an idea on how you should be tightening the top 17mm nut.
Feel free to call if you need clarification."
TOMMY: "Hi Arjay,
Thanks for the help. I think maybe there was a loose nut, but the noise went away by itself. The other day when I was driving it, I did not notice anymore noises.
Tommy" -- Tommy 01/31/2011
5) Here are a few forum links to customers who have had issues with their aftermarket coil-over kits on McPherson strut vehicles:
The following link shows their proposed solution which involves adding a spring isolator, which is basically an ABS plastic ring between the spring and upper and lower perches to help alleviate the binding of the spring and the noise associated with the spring un-binding itself. This ABS plastic ring is already included in our coil-over damper kits and are available for purchase for purposes of replacement. Due to the forces exerted on the ABS plastic ring, it is considered a wear and tear item just as pillow ball mounts are.
6) MICHAEL: my front right coilover on my 2006 mini cooper s is making quite
TECH SUPPORT: McPherson struts can be a pain sometimes. Have you tried tightening the top 17mm nut?
Here is a link showing how to tighten the 17mm nut.
Feel free to give me a call if you have questions.
MICHAEL: Thanks for the link, that’s exactly what it turned out to be. A $10 wrench was a pretty inexpensive repair. I hadn’t looked there because I never touched those nuts. Thanks again for the help, Michael
Arjay, Thanks for all the help. I’ll definitely include tightening those nuts on my maintenance list. You may want to include a note in your FAQ or how-to that these nuts can work themselves loose. If I would have seen that I might have tried tightening them before bothering you guys. Thanks again, Michael.
7) I am glad some people are aware of the issues with the suspension on McPherson strut designs. For the sake of customers who refuse to believe this is a design issue and not a fault of our coil-overs, here is an except from a forum by a knowledgeable forum member who describes why these issues happen and why you cannot fix the issue 100% of the time:
"it is not uncommon for the rsx to have the noise you are describing due to spring bind, especially with after market suspensions. Mine does on occasion, seems to be worse when it is colder. This is my understanding of what is happening. When you turn your tie rod end pushes on the bottom of your strut which is attached to your spindle. So the bottom of the strut rotates along with the spindle. The bottom of the spring sets on the bottom spring perch and it rotates along with the bottom of the strut. Your car is setting on the top of the spring with the top perch and the strut bearing in between. The spring is wanting to rotate but the car does not and the bearing should allow the spring to rotate freely. Well the bearing doesn't spin as freely as we would like so a small amount of tension builds up from the bottom of the spring to the top because the bearing isn't as free as we would like. This tension is spring bind. As we keep turning the bind builds up the the point that the spings slips on the perch or the perch on the brg and it make the clunk noise. Or the bearing starts to rotate and the tension can also be stored after turning then clunk later as we begin to move. Acura tried to address the issue with ball bearing in the 05-06 but it didn't solve the problem. I have relubed mine, added graphite (a suggestion on the Hotchkiss install instruct.) tried lighter lube and it will get better for a while then come back. There are a number of threads on crsx on this. I now just live with it. It doesn't seem to hurt anything, just sounds like shit."
A clunk on the front of a McPherson can be any number of things, as mentioned before, I would check these in the following order:
1) The top 17mm nut, is it loose? Tighten it to be sure. A 5mm hex tool/allen head will be required for this step.
2) If not #1, removal and disassembly of the coilover is required to check the following:
a) Pillow Ball mount-- there should be no play. It can pivot as it is a pillow ball, but the pillow ball itself should not have any play within its housing.
b) Upper and Lower bearing that is inserted into the pillow ball. Check for out-of-roundness, it should fit flush into the pillow ball mount.
c) If none of those are suspect, the strut itself may have incurred internal damage. If this is the case, the strut needs to be discharged and disassembled in order to be diagnosed.
|Q||The Internals of a Muffler Canister|
Have you ever wondered about the construction of a muffler? Well, now is your opportunity to find out. This is not the same for every muffler out there of course-- there will always be other designs that claim to flow better than others. The idea of a muffler is to reduce extraneous exhaust noise while keeping exhaust flow efficient.
The inlet pipe diameter is the same throughout the muffler, however the internal pipe is baffled. This baffled pipe is then wrapped in steel wool which is then wrapped in fiberglass.
Here is an internal view of the muffler with part of the canister cut out to show the construction:
NOTE: The inside view is from the inlet side towards the outlet side. There is a silencer installed in this display muffler.
Here is a video we found that clearly shows the workings of a muffler and the sound waves visually in a video:
|Q||Are Megan Racing exhaust products street-legal?|
All Megan Racing Exhaust and Suspension products are deemed for "off-road use only"-- please check local laws regarding the modification of the exhaust systems by checking the vehicle code for your state. Many states are more stringent on exhaust modification laws and to pass SMOG. Please check local laws. The following information pertains to California residents:
California's Laws Regarding Modified Exhaust:
(b) Except as provided in Division 16.5 (commencing with Section 38000) with respect to off-highway motor vehicles subject to identification, every passenger vehicle operated off the highways shall at all times be equipped with an adequate muffler in constant operation and proper maintained so as to meet the requirements of Article 2.5 (commencing with Section 27200), and no muffler or exhaust system shall be equipped with a cutout, bypass, or similar device. (c) The provision of subdivision (b) shall not be applicable to passenger vehicles being operated off the highways in an organized racing or competitive event conducted under the auspices of a recognized sanctioning body or by permit issued by the local governmental authority having jurisdiction.
(b) The Department of Motor Vehicles may accept a dealer's certificate as proof of compliance with this article. (c) Test procedures for compliance with this article shall be established by the Department of the California Highway Patrol, taking into consideration the testing procedures of the Society of Automotive Engineers.
(1) Sound Level Limit. The exhaust noise shall not exceed 95 dB(A).
This is very straightforward and should leave nothing to interpretation.
|Q||BBK: What size wheels will the GT-200 will fit?|
The physical dimensions of the caliper and brake pad for the GT-200 model big brake kit are found in the following photo.
The GT-200 big brake system requires a minimal wheel diameter of 18" and caliper to spoke clearance depends on wheel style and offset. In order to confirm wheel clearance, print out the following photo, cut along the perforated / dashed line and prop against the intended wheel to check clearance.
|Q||BBK: Why sliding calipers are bad?|
|A||Generally, most vehicles are equipped with 4-wheel disc brakes standard. A few years ago, you would be lucky to find disc brakes on all four corners. With performance vehicles, more and more are arriving brand new from the factory with mono-block calipers and are 4-pot. However, most vehicles on the street are still using sliding caliper mechanisms. These sliding caliper mechanisms have certain drawbacks, most of which are examined here. In the picture, we see a typical set of used brake pads on a vehicle with a sliding caliper mechanism. A sliding caliper is a two piece calipre with a single piston. Between the two pieces of the caliper are slider pins that allow for the assembly to clamp down on the rotors. One main drawback of sliding caliper brake systems is uneven pad wear, among other things. For purposes of this article, we will focus on uneven pad wear. Notice that the pads are not weairng evenly, which insists that the sliders need to be cleaned and greased to ensure proper function. The benefit of our brake systems is that this sliding caliper mechanism is alleviated with a mono-block caliper construction. Instead of a single piston, piston size is smaller, but the quantity is increased to a 4-pot (4 pistons) or 6-pot (6 pistons) design for even pad distribution on the rotor. The results are more consistent braking performance under extreme heat conditions, such as track use, more even brake pad wear and therefore increased longevity of the braking system. With the purpose of making a vehicle as efficient as possible, the big brake kits we offer provides an obvious choice on the next modification to your vehicle. Please contact your sales representative for purchasing information or our tech department for any questions.|
|Q||CDK: Pillow Ball Mount Information|
On McPherson strut suspension (typical examples include 1989+ Nissan 240SX, Subaru Impreza 93+, Mitsubishi Lancer EVOLUTION 8, 9 and 10, etc), the front strut is secured to the camber plate via pillow ball mount and typically the pillow ball mount is a universal application-- the ID of the pillow ball mount is M14, for most of the coil-over applications. However, there are a few isolated applications that use a special/unique pillow ball mount that is not the same as the rest.
There are seven different types of pillow ball mounts used:
1. Standard, the most commonly used.
2. Honda Beat (international application only)
3. 2000+ Toyota MR-S
4. 1990 Toyota MR-2 / 2002-2006 Acura RSX (DC5)
5. GDB/GDF Rear
6. 1994 Dodge NEON Rear
7. BMW E36/E46
Pictured on the left (1.75") is one of the non-universal application pillow ball mounts, specifically it is for the 1990 MR-2 / Acura RSX DC5. Pictured on the right (2 5/16") is a universal application pillow ball mount and is most commonly used among the other applications. Notice the difference between the distance between the mounting holes. Aside from this difference, one of the main features of the unique pillow ball mounts are that the upper surface of the mount is flush while the universal mount is not.
This informational article is provided for your reference when purchasing replacement parts to help assure that you order the correct part for your application.
|Q||CDK: Damper Setting Information|
We often get questions regarding the best damper settings for their vehicle and for their intended use. It is often mis-understood that dampers have a “set it and forget it” setting. The truth of the matter is that they are adjustable for a reason, whether it be to make necessary damping adjustments to a spring rate change to fine tuning the handling characteristics of the vehicle. These topics of damper settings will be addressed in this article.
An important issue with the damper adjustments available is how to find the settings. When in doubt, it is best to rotate the damper knob towards the STIFF setting, which is by rotating the knob clockwise. There is a physical limitation towards the STIFF setting, while there is no physical limitation towards the SOFT setting, which is why it is extremely important not to exceed the amount of clicks going towards the SOFT setting as it may upset the shim-stack alignment within the strut or shock internals and may result in damage to the damper internals. At this point, a third-party re-valve may be necessary. Should the customer find a custom re-valve of the shock necessary, we offer shock cartridge insert replacements and often keep these in stock for quick replacement for the customer. Keeping replacements for each and every application would be impossible, though we do our best, so please check with us as far as availability for each specific component you may need.
To set the damper, we suggest rotating the knob full clock-wise towards FULL STIFF and counting back the clicks counter-clockwise until you find the desired setting. For strut/shocks with 32-way adjustability, this means when the knob is adjusted to full stiff, you can count back 32-clicks to find the softest setting, but it is critically important for the life of the strut/shock that this limitation is not exceeded to prevent against internal damage within the strut/shock.
First and foremost, all of our coil-over line-ups feature 32-way adjustability, except for our newest line-up, the EZ-Streets, which are 15-way adjustable. As stated in the item descriptions for the EZ-Street coil-over applications, the valving characteristics between the EZ-Street Series and STREET Series coil-overs are the same, while the only difference being 15-way vs 32-way adjustable. This is simply to allow for finer damper adjustments should the user call for it. In essence, the max and min settings are similar (as long as they share the same valving code) and these would be reflected in the dyno plots provided for each damper, however one would take more clicks to reach the maximum and minimum settings compared to the other.
Changes between each click are sometimes so minute that you will not feel these differences back to back on the vehicle as there are several variables to consider when feeling for the differences. These would inevitably become apparent on an extensive dyno plot where the dyno is meticulously dyno’d at each individual click.
For the purpose of the general user with limited experience with adjustable shocks, we provided a very generic outline of the damper settings:
1-8: Suggested for track use.
These settings are for generic purposes and should not necessarily be the end-all setting suggestion, but merely as a point of comparison to help understanding the nature of the strut/shock valving characteristics. With that said, while 1-8 is “suggested for track use,” you may very well find a softer setting may be more ideal for your particular vehicle, suspension setup, tire compound and driving style. Again, these are generic recommendations and should only be noted as a baseline.
To further understand the purpose of an adjustable strut/shock, one must understand exactly what it does. During the R&D phase of the development of a coil-over damper kit, spring rates are chosen based on the front to rear weight distribution and the front and rear wheel motion ratios to determine the potential ride frequencies of the vehicle that would result from the selection of certain spring rates. Once the spring rate is determined for the particular application, the valving code is determined accordingly to handle the specific spring rate. The strut/shock valving deals primarily in controlling the spring, not necessarily the vehicle—again the spring rates are determined by factors of the vehicle, which is why some applications feature the same spring rate on all four corners, while some use heavier springs up front and some applications use heavier spring rates in the rear. In layman’s terms, the strut/shock’s sole responsibility is to critically dampen the spring oscillations and keep the spring under control during compression and especially during rebound of the spring. When a bump in the road is encountered, the energy of the wheel and suspension is transmitted to the spring, which causes the spring to compress a certain amount. This energy is stored in the spring during the compression stage of the spring and results in the decompression of the spring, or the lengthening of the spring back to free-length. The damper’s job is to absorb the energy transmitted from the compression of the spring to reduce extra oscillations of the spring that would inevitably be transferred to the vehicle resulting in undesirable handling characteristics.
Once these characteristics are well understood, we are ready to move onto properly tuning the damper. For an intermediate user, tuning primarily for street use, the main thing to tune out for is making sure the suspension is not under-damped, not over-damped, but critically damped. What this means is that the damping needs to be set to properly dampen the spring oscillations. If the spring is under-damped, the spring will continue to oscillate a few times after the initial compression. This results in a bouncy ride, which can be very uncomforting and potentially dangerous. The over-damped situation can occur with the settings adjusted too stiff than what is necessary to control the spring oscillations. When the spring compresses and then rebounds, the shock is over-damping the spring and is surpassing the spring frequency, which will result in what feels like a stiff ride. Looking closer at an over-damped situation, the shock would be too aggressive for the spring and can result in loss of tire traction over rough and uneven surfaces by not letting the wheel conform to road undulations. This can be equally dangerous as sudden traction may be lost—this is critical to handling performance as an over-damped situation would result in less overall grip of the vehicle.
When one understands the concepts of a critically damped suspension, they will be able to further fine tune what the suspension is doing and further adjust the strut/shock damping to cater to his/her own driving preferences. Damper adjustments also have an effect on the handling characteristics of the vehicle as a whole and therefore also provide another means of tuning out under steer and over steer tendencies. For advanced users, they may fine-tune the shocks to cater to their driving style, whether they prefer a more under-steer-prone vehicle or a more over-steer-prone vehicle. Of course, these under steer and over steer tendencies are attributed to the entire suspension package and vehicle setup—not just the dampers. The dampers should be used to fine-tune the vehicle when everything else in the vehicle setup is tuned accordingly.
|Q||CDK: Thread Pitch|
We have had several requests for the thread pitch of the shock bodies of our coil-over assemblies.
|Q||Miata Headers Identification Guide|
1990-93 Miata 1.6L - No EGR fitting required
1994-97 Miata 1.8L - Male EGR Fitting Provided, On #3 Primary Tube
1999-00 Miata 1.8L - Female EGR Fitting, Provided On Header Flange
2001-05 Miata 1.8L - Male EGR Fitting, Provided On Header Flange
Monday, December 23, 2013: Message RE: E46 M3 coilover issue; clunking
Greetings Brennan, If the adjustor knob came off, it got loose and worked its way off. I always recommend keeping them tight regularly and all the more important for the top 17mm nut tight. The top nut being loose can be the cause of any clunking.
Thank you, I had a shop look at it and confirm it was the strut nut that came loose. They tightened it right up and the noise is gone. Thank you for your help, and your product is awesome. - Brennan M.
Wednesday, December 18, 2013: Message RE: Coil-Bind
Saturday, December 15, 2013: Message RE: Subaru Impreza WRX /STi 2008-2010 P#: SB-HBSI08
2) Greetings Simon, When you took this picture, were the other mounting points for the brace fully tightened down? Please loosen all mounting points and then thread the hardware on each mounting point slowly and little by little, evenly tightening it down.
3) Thanks. Fit well! --Simon T.
MORAL OF THE STORY: Many fitment issues arise from installation inexperience and are not necessarily an issue and/or a manufacturer defect.
Sunday, May 12, 2013: Message RE: Lowering Springs:
Monday, May 6, 2013: Message RE: Clunking Noise on CDK:
Wednesday, April 24, 2013: Message RE: Customer Service: MR-SSH-HP97NS Prelude Header being out of stock.
Tuesday, April 9, 2013: Message RE: MRS-HA-1521
Monday, April 1, 2013: Message RE: MR-ABE-HF07
Wednesday, November 14, 2012: Message RE: Exhaust for VW 2.0 FSi
Friday, May 4, 2012: Message RE: pillow ball mounts
Wednesday, April 4, 2012: Message RE: MR-SSH-HP92
Wednesday, March 21, 2012: Message RE: MR-CDK-N3Z rear springs
Tuesday, January 24, 2012: Message RE: MR-6401-RF
Monday, January 23, 2012: Message RE: MR-CDK-MMX590-EZ
Tuesday, January 4, 2012: Message RE: Lowering Springs
Monday, December 12, 2011: Message RE: Lowering Springs Clunking
Greetings Michael, I would make sure your top hats are assembled correctly. There is no reason for the spring to be making any sort of noises since it is held securely in place by the weight of the vehicle.
Sunday, November 20, 2011: Message RE: Clunking
Tuesday, August 9, 2011: Message RE: Lowering Spring Installation
Saturday, August 6, 2011: Message RE: Top clunks.
Thanks for the quick response. I checked that 17 mm and now both noises are gone! It figures the 1 bolt me and the guy at the dealer didn't check was the cause. Sad thing is I had the hood open and checked the 3 12mm but didn't see the 17 before I went to to shop. Thanks, Steve S.
Wednesday, August 3, 2011: Message RE: Megan Racing TRACK SERIES coil-overs
Friday, July 22, 2011: Message RE: MR-CDK-SI02 Rear Camber Adjustment
Sounds good. Thanks. You have been a great help.
Another question. Do you think that it would be better to put rear camber plates instead of just the regular top hat? That's what a friend was telling me just curious. Anthony.P
Monday, July 18, 2011: Message RE: Custom coil-over setup
Wednesday, June 29, 2011: Message RE: Stainless Steel and Warranty
Thursday, June 23, 2011: Message RE: Replacement strut/shock
Thursday, June 16, 2011: Message RE: McPherson Strut Noises
Friday, June 10, 2011: Message: RE: MR-CDK-PGTO:
Friday, May 20, 2011: Message: RE: MR-SB-S2KFU:
Wednesday, May 4, 2011: Message: RE: MR-CDK-HC01:
Thursday, April 28, 2011: Message: RE: MR-MG-OP:
Thursday, March 31, 2011: Message: RE: MR-CDK-LSC3-EZ:
Mon, Apr 04, 2011 9:23 pm: Message: RE: MR-CDK-NS14:
Mon, March 21, 2011 10:25 am:
Tue, Jan 18, 2011 9:17 pm: Message: RE: MR-CDK-N3Z-RS:
At the track I started out kinda high on the settings, not wanting to chase them all afternoon. Fronts and rears were set to 4 clicks down from full stiff for both rebound and compression. The tires I used were a new set of Falken Azenis 615s (new but the older discontinued compound). On track I immediately noticed the new behaviors, rock stable. They didn't feel under or over dampened, well matched springs rates to the shocks. Turn in was nice and didn't exhibit excessive roll (however, more roll than what I remember with the last set of Swift Springs and stock shocks. I'm attributing this to a taller ride height and stickier tires). On the banking it was very well balanced and I ended up carrying 15 mph more corner speed at the fastest point on the banking. Very confidence inspiring. Braking was dramatically more composed than the spring set up I had previously. At speed the dampening was very comfortable (not harsh, but still controlled). The only section I had a problem with was a rippled area on the infield straight. The rear wheels would take the shock of the undulations and cause problems shifting (due to the violent movement of the shocks). To combat this I took out 3 clicks of both rebound and compression in the rear. This helped quite a bit to remove the problems in this one area but hurt in a variety of other corners. The car became less stable on the banking and overall had an fair bit more movement (mostly roll). Considering that BC ER plot I immediately remembered how sensitive the adjuster was in this area of the adjustments plots. I assumption of the fault is based on what you told me when you saw the plots initially, the linear/progressive nature of the shock will give you a little problem on the rough tracks. Considering I'm still on the stock sway bars I think a little more bar can go a long way to being a band-aid for this issue.
Overall, I'm happy with the kit (after changing to the 210 mm spring). Fit and finish are good, no clunking, very smooth for such a high spring rate (12k and 10k) and they didn't fade at any point in the running. For me it was between these and a set of KW's. I knew the KW V3s would be too soft and I would have to send them back for a re-valve and new springs only adding to the total cost (some $800+ the cost of the kit). So my decision was made easy after recognizing what spring rate would be best for me. Another con is the compression adjusters are kinda tough to ge to but that's only nit picking. Now, if they only were a little more digressive and didn't ramp up so high on the med to high speed impacts. -Mike J.
|Q||CDK: Spanner Wrench Dimensions|
Most of our spring perches utilize the following spanner wrench dimensions. This applies to EZ Streets, STREET Series, TRACK Series, EURO Street Series, and STREET-LP Series. Our Spec RS series requires different sized spanner wrenches. Also, some applications that utilize a rear spring bucket where the spring is not mounted over the shock body may have vehicle-specific sized spanner wrenches.
It is good practice to make sure that the spanner wrenches are securely fastened onto the locking spring perches to make sure it does not damage the teeth of the spring perches and/or damage the spanner wrenches themselves. We also sell these spanner wrenches separately in case you need to replace a set of spanner wrenches.
Wrenches that look like the ones pictured above are normally stocked, and other spanner wrenches for certain applications that need special sized spanner wrenches are available for special order as well.
|Q||TECH: Basics of a 4-wheel Alignment|
Wheel alignment is a critically important aspect of a vehicle and should be addressed whenever the suspension of the car is altered in any way. Even unbolting a shock from the vehicle may throw off the alignment enough to affect the cornering performance of the vehicle as well as the tire life. Whether you are racing against the clock on a road course, or simply communiting in your daily driver, alignment is a necessary aspect of automobile tuning.
A few terms associated with alignments include: camber, caster, toe, steering axis of inclination (SAI), included angle, scrub radius, riding height (also known as static ride height), set back, thrust angle, steering center, and toe out in turns. Many of these terms are not adjustable, however, but are good to know about regardless. Only in some vehicle applications can changes be made. For the purpose of tire wear as a main priority, camber and toe are the most important factors-- not all of these terms need to be addressed for a wheel alignment. Even in proper race car setup, all of these terms are addressed in the setup, but not all of them are necessarily adjusted. We will go through each term and its definition.
When camber specifications are determined during the design stage of an automobile, a number of factors are taken into account. The engineers account for the fact that the wheel alignment specifications used by alignment technicians are for a vehicle that is not moving. On many vehicles, camber changes with different road speeds. This is because aerodynamic forces cause a change in riding height from the height of a vehicle at rest. Because of this, riding height should be checked and problems corrected before setting camber. Camber specs are set so that when a vehicle is at highway speed, the camber is at the optimal setting for minimum tire wear.
For many years the trend has been to set the camber from zero to slightly positive to offset vehicle loading, however the current trend is to slightly negative settings to increase vehicle stability and improve handling. The camber is the angle of the vertical plane the wheel and tire creates, perpendicular to the horizontal ground. Typical camber settings on factory vehicles range from 0 degrees to 1 degree negative camber. The degree or so of negative camber helps maintain the contact patch of the tire under cornering loads.
On race car applications, it is not uncommon to see larger amounts of negative camber due to different tire compounds utilized that favor maximum tire grip and traction levels over tire wear and longevity. There are no "set-in-stone" camber settings for any application or vehicle as the design of the suspension geometry of the vehicle is just as important as the tire compound being used. A tire pyrometer is often used by race teams to measure the tire tread temperatures on the inner, middle and outer tread blocks after coming in from a hot lap-- if you take a cool down lap, tire temperatures are bound to decrease and therefore the data you collect would be inaccurate. The tire temperatures are taken on all four corners, starting from the hotter side first as tire temperatures drop dramatically. The differences between the inner, middle and outer tread blocks can help determine if more camber is necessary to keep the tire from rolling over, or if the camber is setup appropriately. The relative tire temperatures on all four corners are also taken into consideration for further suspension tuning diagnosis, as well as driver inputs. For example, if the front tire temperatures are higher than the rear, it may indicate a "push" situation where the car is understeering which can point to poor suspension setup, as well as bad driver inputs (over driving the vehicle and/or setup). In contrast, if the rear tires are higher than the front, it can denote an oversteer scenario, where the driver may need to lay off the throttle.
Positive caster improves straight line tracking because the caster line (the line drawn through the steering pivot when viewed from the side) intersects the ground ahead of the contact patch of the tire. Just like a shopping cart caster, the wheel is forced behind the pivot allowing the vehicle to track in a straight line.
If this is the case, then why did most cars have negative caster specs prior to 1975? There are a couple of reasons for this. In those days, people were looking for cars that steered as light as a feather, and cars back then were not equipped with radial tires. Non-radial tires had a tendency to distort at highway speed so that the contact patch moved back past the centerline of the tire (Picture a cartoon car speeding along, the tires are generally drawn as egg-shaped). The contact patch generally moves behind the caster line causing, in effect, a positive caster. This is why, when you put radial tires on this type of car, the car wanders from side to side and no longer tracks straight. To correct this condition, re-adjust the caster to positive and the car should steer like a new car.
In a passenger vehicle, caster is not as important as camber and toe settings, but is something to consider, especially in McPherson strut applications, where struts are used in the front suspension as opposed to double wishbone or other multi-link suspension setups. In McPherson strut setups, higher positive caster numbers can help with straight-line stability. These caster numbers are also adjusted to influence the way the vehicle reacts in motorsports. For example, in drifting, higher caster numbers are generally favorable to aid in centering the steering wheel between directional transitions. In racing, caster numbers can influence high-speed straight line stability.
Like camber, toe will change depending on vehicle speed. As aerodynamic forces change the riding height, the toe setting may change due to the geometry of the steering linkage in relation to the geometry of the suspension. Because of this, specifications are determined for a vehicle that is not moving based on the toe being at zero when the vehicle is at highway speed. In the early days prior to radial tires, extra toe-in was added to compensate for tire drag at highway speed.
On some older alignment machines, toe-in was measured at each wheel by referencing the opposite wheel. This method caused problems with getting the steering wheel straight the first time and necessitated corrective adjustments before the wheel was straight. Newer machines reference the vehicle's centerline by putting instruments on all four wheels. For more information on this see "Steering Angle" and "Thrust Angle."
For optimal tire wear settings, where tire conservation is the top priority, zero toe is ideal as the tires will be traveling parallel to each other, producing the least tire drag and rolling resistance. Toe can be set "in" or "out" as well to influence the vehicle's behavior in motorsports use. For example, in front-wheel-drive vehicles, which tend to have problems with understeer, toe-out is used to help promote proper "turn-in" at corner entry. Of course, these settings will always have compromises as a toe-out alignment may cause for a twitchy steering wheel at high speeds. Likewise, for rear-wheel drive vehicles that are very oversteer-prone, tuners may dial in some toe-in in the rear wheels to add some rear end stability.
STEERING AXIS OF INCLINATION (SAI)
SAI is the measurement in degrees of the steering pivot line when viewed from the front of the vehicle. This angle, when added to the camber to form the "included angle" (see below) causes the vehicle to lift slightly when you turn the wheel away from a straight ahead position. This action uses the weight of the vehicle to cause the steering wheel to return to the center when you let go of it after making a turn. Because of this, if the SAI is different from side to side, it will cause a pull at very slow speeds. Most alignment machines have a way to measure SAI; however it is not separately adjustable. The most likely cause for SAI being out is bent parts which must be replaced to correct the condition. SAI is also referred to as KPI (King Pin Inclination) on trucks and old cars with king pins instead of ball joints.
Included angle is the angle formed between the SAI and the camber. Included angle is not directly measurable. To determine the included angle, you add the SAI to the camber. If the camber is negative, then the included angle will be less than the SAI, if the camber is positive, it will be greater. The included angle must be the same from side to side even if the camber is different. If it is not the same, then something is bent, most likely the steering knuckle.
Scrub radius is the distance between where the SAI intersects the ground and the center of the tire. This distance must be exactly the same from side to side or the vehicle will pull strongly at all speeds. While included angle problems will affect the scrub radius, it is not the only thing that will affect it. Different wheels or tires from side to side will cause differences in scrub radius as well as a tire that is low on air. Positive scrub radius is when the tire contact patch is outside of the SAI pivot, while negative scrub radius is when the contact patch is inboard of the SAI pivot (front wheel drive vehicles usually have negative scrub radius).
If the brake on one front wheel is not working, with positive scrub radius, stepping on the brake will cause the steering wheel to try to rip out of your hand. Negative scrub radius will minimize that effect.
Scrub radius is designed at the factory and is not adjustable. If you have a vehicle that is pulling even though the alignment is correct, look for something that will affect scrub radius.
STATIC RIDE HEIGHT:
Riding height is measured, usually in inches, from the rocker panel to the ground. Good wheel alignment charts provide specs, but the main thing is that the measurements should be within one inch from side to side and front to rear. Riding height is not adjustable except on vehicles with torsion bar type springs. The best way to fix this problem is to replace the springs (Note: springs should only be replaced in matched pairs). Changes in riding height will affect camber and toe so if springs are replaced or torsion bars are adjusted, then the wheel alignment must be checked to avoid the possibility of tire wear. It is important to note that the only symptom of weak coil springs is a sag in the riding height. If the riding height is good, then the springs are good.
Set back is when one front wheel is set further back than the other wheel. With alignment equipment that measures toe by using only the front instruments, any setback will cause an uncentered steering wheel. Any good 4-wheel aligner will reference the rear wheels when setting toe in order to eliminate this problem.
Some good alignment equipment will measure set back and give you a reading in inches or millimeters. A set back of less than 1/4 inch is considered normal tolerance by some manufacturers. More than that and there is a good chance that something is bent.
Thrust angle is the direction that the rear wheels are pointing in relation to the center line of the vehicle. If the thrust angle is not zero, then the vehicle will "dog track" and the steering wheel will not be centered. The best solution is to first adjust the rear toe to the center line and then adjust the front toe. This is normally done during a 4-wheel alignment as long as the rear toe is adjustable. If the rear is not adjustable, then the front toe must be set to compensate for the thrust angle, allowing the steering to be centered.
Steering center is simply the fact that the steering wheel is centered when the vehicle is traveling down a straight and level road. A crooked steering wheel is usually the most common complaint that a customer has after a wheel alignment is performed. Assuming that the steering wheel stays in the same position when you let go of the wheel (in other words, the car is not pulling), then steering center is controlled by the front and rear toe settings. When setting steering center, the rear toe should be set first bringing the Thrust Angle as close to the vehicle centerline as possible. Then the steering wheel is locked in a straight ahead position while the front toe is set. Before locking the steering wheel, the engine should be started and the wheel should be turned right and left a couple of times to take any stress off the power steering valve. After setting the toe, the engine should be started again to be sure that the steering valve wasn't loaded again due to the tie rod adjustments. Of course, you should always road test the vehicle after every alignment as a quality control check.
Another problem with steering center has to do with the type of roads that are driven on. Most roads are crowned to allow for water drainage, and unless you drive in England, Japan or another country where they drive on the wrong (sorry) left side of the road, you usually drive on the right side of the crown. This may cause the vehicle to drift to the right so that the steering wheel will appear to be off-center to the left on a straight road. The best way to compensate for this is as follows:
TOE OUT ON TURNS:
When you steer a car through a turn, the outside front wheel has to navigate a wider arc then the inside wheel. For this reason, the inside front wheel must steer at a sharper angle than the outside wheel.
Toe-out on turns is measured by the turning angle gauges (turn plates) that are a part of every wheel alignment machine. The readings are either directly on the turn plate or they are measured electronically and displayed on the screen. Wheel alignment specifications will usually provide the measurements for toe-out on turns. They will give an angle for the inside wheel and the outside wheel such as 20º for the inside wheel and 18º for the outside wheel. Make sure that the readings are at zero on each side when the wheels are straight ahead, then turn the steering wheel so that the inside wheel is at the inside spec. then check the outside wheel.
The toe-out angles are accomplished by the angle of the steering arm. This arm allows the inside wheel to turn sharper than the outside wheel. The steering arm is either part of the steering knuckle or part of the ball joint and is not adjustable. If there is a problem with the toe-out, it is due to a bent steering arm that must be replaced.
|Q||The Truth about Stainless Steel|
In metallurgy, "stainless steel" is defined as a steel alloy with a minimum content of 13.0% chromium by mass. Stainless steel does not stain, corrode, or rust AS EASILY as ordinary steel, but it is NOT stain-proof. There are different grades and surface finishes of stainless steel to suit the environment to which the material will be subjected to in its lifetime. Stainless steel is used where both properties of steel and resistance to corrosion are required.
In the automotive industry, a cheaper, more commonly used alternative to stainless steel is mild steel, or carbon steel. Carbon steel, also called plain-carbon steel, is steel where the main alloying constituent is carbon. The American Iron and Steel Institute (AISI) defines carbon steel as: "Steel is considered to be carbon steel when no minimum content is specified or required for chromium, cobalt, columbium, molybdenum, nickel, titanium, tungsten, vanadium, or zirconium, or any other element to be added to obtain a desired alloying effect; when the specified minimum for copper does not exceed 0.40 percent; or when the maximum content specified for any of the following elements does not exceed the percentages noted: manganese 1.65, silicon 0.60, copper 0.60."
The term "carbon steel" may also be used in reference to steel which is not stainless steel; in this use carbon steel may include alloy steels. As the carbon content rises, steel has the ability to become harder and stronger through heat treating, but this also makes it less ductile. Regardless of the heat treatment, a higher carbon content reduces weldability. In carbon steels, the higher carbon content lowers the melting point. Eighty-five percent of all steel used in the United States is carbon steel.
Stainless steel differs from carbon steel by the amount of chromium present by percentage of its mass. Carbon steel oxidizes when exposed to air and moisture. This iron oxide film (the rust) is active and accelerates corrosion by forming more iron oxide. Stainless steels contain sufficient chromium to form a passive film of chromium oxide, which prevents further surface corrosion and blocks corrosion from spreading into the metal's internal structure.
High exidation-resistance in air at ambient temperature is normally achieved with additions of a minimum of 13% (by weight) chromium, and up to 26% is used for harsh environments. The chromium forms a passivation layer of chromium (III) oxide (Cr2O3) when exposed to oxygen. The layer is too thin to be visible, and the metal remains lustrous. The layer is impervious to water and air, protecting the metal beneath. Also, this layer quickly reforms when the surface is scratched. This phenomenon is called passivation and is seen in other metals, such as aluminum and titanium. Corrosion-resistance can be adversely affected if the component is used in a non-oxygenated environment, a typical example being underwater keel bolts burried in timber.
Megan Racing exhaust products are manufactured using SUS/T-304 Stainless Steel. Grade 304 steel is the standard "18/8" stainless steel; it is the most versatile and most widely used stainless steel, available in a wider range of products, forms and finishes than any other. The "18/8" stands for the chromium and nickel content of the steel. Grade 304 stainless steel contains 18-20% chromium, which is the main element that gives this grade of steel the corrosion resistance it has. It has excellent forming and welding characteristics. With all that said, just because an item is T-304 Stainless Steel, does not mean that the material is 100% stain or corrosion proof. It is merely more resistant to staining and corrosion. The weather and environment with higher than normal humidity and precipitation figures allow the steel to be more prone to rust and corrosion, but 304 stainless steel is NOT rust-proof.
Many people question if we truly do use 304 Stainless Steel or not. For this reason, here is a photo of prototype piping that has not been polished as all of our final production pieces are. This should clear up any confusion as to the materials we use for our exhaust system products:
|Q||To corner-balance, or not to corner balance?|
So what does all of this have to do with Megan Racing suspension components? The fact of the matter is, all of our coil-over line ups from the EZ-street coil-overs to the Spec-RS series are dual-adjustable with separate spring pre-load adjustments as well as shock length adjustability. While spring pre-load adjustment is does not need to be adjusted more than once, unless a different spring length is used, the shock length feature is critical and allows for corner balancing without affecting spring pre-load which may compromise shock travel. When a car is corner balanced, the shock heights are adjusted on each particular corner to balance the cross weights-- meaning the shock lengths are not the same on both rear corners nor on the front. As seen in the above photo, the left side of the vehicle carries more weight than the right side and has a cross weight of 54%-- all prior to corner balance adjustment. Corner balancing necessitates for shock length adjustments on each individual corner to change the effective weight resting on each tire's contact patch. Without shock length adjustability, the height would have to be adjusted through the perches that affect spring pre-load and will compromise (READ: Lose) valueable shock travel.
While it is not absolutely necessary for our customers to corner balance their vehicles after installation of our fully adjustable coil-over kits, we do recommend it to maximize the performance characteristics of their suspension. The need for corner balancing depends on the intended use of the vehicle. During normal daily driving on the street, you probably would not be able to realize the benefits of a corner balanced vehicle anyway, but this is always recommend for a track-driven vehicle. Once a vehicle is corner balanced, we see a drastic improvement in the three aspects of corner weight, particularly in the cross weight percentage. Compare the previous photo with the inital weights at each corner with the following photo. Pay particular attention to the three aspects of corner balance:
Along with fully adjustable suspension and corner balancing, the car will benefit from adjustable endlinks to zero out the pre-load on the front and rear sway bars. The reason behind this is, as a result of corner balancing, the suspension on some corners will be longer than other corners and with a single sway bar connecting both sides of the suspension connected by fixed endlinks, there is a potential that the sway bar is loaded one way. The goal is to have sway bars that are zero-pre-loaded so that the handling characteristics would be symmetrical between LEFT turns and RIGHT turns.
|Q||BBK: Big Brake Kit FAQ|
Q: Do I need a big brake kit?
A: Modern OEM brake systems found in vehicles today work well for the most part for typical daily driving stopping necessities such as single 80-0 or 60-0 stops and average daily driving. Meanwhile, the typical automotive enthusiast can easily overwork the stock brake system beyond its natural capabilities. This problem can be easily exacerbated once the vehicle is modified to make more power. OEM brakes can typically be overheated from a few repeated stops which can potentially cause more problems within the braking system such as boiled fluid, glazed pads, and distorted calipers. Megan Racing's big brake kits will provide increased heat capacity which means more resistance to brake fade and caliper distortion with multiple stops from high speeds. A firmer pedal feel and brake modulation under threshold braking are also benefits of a properly balanced braking system.
A: Megan Racing big brake kits are designed using the latest technology and the strongest materials possible for the application of the brake system, where the strength and heat dissipating capabilities are the most important aspects of the materials used. High precision 3D CNC machined mono-block calipers are forged out of aircraft T2024 aluminum allow with forged internal hydraulic circuit design. T2024 aluminum is known for its strength to weight ratio for aluminum alloys. This is particularly important to keep the weight of the caliper low to keep un-sprung weights at a minimum to maximize performance. Unsymmetrical piston sizes are utilized for linear braking performance. For our GT-200 big brake upgrade, a 2-piece floating rotor design is used to cool more efficiently than traditional 1-piece rotors due to less restrictive airflow though directional vanes. The reusable rotor hats are constructed out of T7075 aluminum.
Q: What do I get with my Megan Racing big brake kits?
A: The contents of the big brake kits vary widely depending on their application. For example, we have front only upgrades as well as complete front and rear upgrades, including upgraded rear calipers as well. We also have individual rear brake upgrades such as for the Nissan 350Z, for which we sell front and rear upgrades separately and as a combo.
Q: Do I need a proportioning valve upgrade with Megan Racing's brake upgrades?
A: Megan Racing's big brake kits are designed to maintain or improve the original brake bias of the stock configuration for each application. Many big brake kits that are not designed properly can degrade the performance of the brake system and even cause the ABS system to malfunction.
Q: Are there any necessary modifications to mount the big brake kit?
A: In a word, no. Our big brake kits come with everything necessary included to complete the big brake upgrade including the pair of forged mono-block calipers, the pair of appropriately sized rotors and pads as well as the brake lines, perfectly engineered to route exactly like the OEM braking system. The installation of the entire big brake kit is a direct bolt-on affair-- high-grade hardware is also included as well. You will need to replace the existing caliper brackets that came on your vehicle and replace with our caliper bracket to mount the caliper to your vehicle.
Q: Why is the pad and rotor break-in procedure so important?
A: PROPER BREAK-IN OF ROTORS AND PADS IS CRITICAL TO MAXIMIZE BRAKING PERFORMANCE. Improper pad and rotor break-in can cause damage to the rotors and adversely affect overal braking performance. The rotor surface may have uneven pad material deposited onto the rotor surface which can impede stopping power. Pads and rotors interact with each other to provide efficient brake performance. The break-in or bed-in procedure is done to condition the pad/rotor interface. Depending on the pad used, more or less pad material is uniformly transferred onto the disc as a thin film. The resins and bonding agents in some pads need to be heat cycled to work properly as well. By not properly bedding in pads, uneven pad material deposits can occur that may cause a vibration. Improper wear characteristics may also show up on either the pads, or rotors, or both, and both will wear prematurely. Always follow the recommended break-in procedure for any pads, rotors or brake systems.
Q: Can I install the brake upgrade on my own?
A: Our braking systems come complete with everything needed to install the system onto your vehicle with the exception of brake fluid; however, due to the nature of the braking system and how crucial it is for the operation of the vehicle, especially for the safety of the driver and the passengers of the vehicle, we STRONGLY recommend professional installation by a shop that is experienced in performance applications. Improper installation of the big brake kit can lead to failure to stop the vehicle and can result in catastrophic failure.
Q: What kind of brake fluid should I use?
A: There are several different manufacturers of brake fluid available. Generally a DOT 4 fluid is sufficient for street use. Any quality name brand or OE brake fluid will be sufficient. If running on an open track, you might want to step up to a racing brake fluid with higher dry and wet boiling points. Megan Racing recommends ATE Super Blue / Type 200 brake fluid which features a higher dry and wet boiling point compared to OE brake fluid. Other notable brands with higher wet and dry boiling points are Motul 600 as well as Castrol SRF, which is easily recognized as the best available brake fluid for professional racing due to its patented and unique chemical composition, though it does carry a heftier price tag. The SRF fluid, along with other DOT 4 and DOT 5 fluids, will need to be more frequently changed as well. Also, when upgrading from the OEM DOT 3 brake fluid to DOT 4 or DOT 5 brake fluids, it is recommended to bleed and flush the brake fluid more regularly as higher DOT fluids tend to absorb moisture more frequently than DOT 3 fluids.
Q: A bigger pad means better braking, right?
A: If you compare two pads, both using the same compound, in the same location but both of different sizes, the smaller pad will not yield shorter stopping distances. What determines the stopping force, or the torque reaction, are the combination of the amount of pressure applied, the friction coefficient of the brake pad, and the diameter of the rotor. A bigger pad does not apply more pressure, only the same pressure over a larger surface area. Where the size of the brake pad matters is in terms of heat capacity and wear rate. A pad with a larger surface area will absorb more initial heat (less thermal shock), and have better wear characteristics (longer pad life).
Q: What are differential bores?
A: Differential bores have to do with the size of the pistons of the caliper, which are used to control brake pad taper. As incandescent material and debris from the leading edge of the pad is trapped between the pad and rotor, it tends to float the trailing edge of the pad off the rotor. A larger piston at the trailing edge of the pad provides more pressure to compensate for this debris buildup and keep the pad flat against the rotor.
Q: Which is better: plain, slotted, or cross drilled rotors?
A: We do not recommend drilled rotors due to the decreased surface area that results from cross drilled rotors. Although most people prefer the aesthetic appeal of drilled rotors, drilling the rotors takes away from the surface area of the rotor which takes away from the contact-patch that is developed between the rotor and the pad. More importantly, the holes on a drilled rotor compromise the construction of the rotors and can lead to warping and/or cracking. In general, less rotor material degrades heat dissipation capabilities of the rotor, which is what leads to overheating rotors. Overheated rotors will warp and will become unusable. Megan Racing will always choose performance and reliability over aesthetics.
Q: How do I tell which directions the rotors are mounted on my car?
A: The interior vanes as well as the direction of the slots on the rotor are what determine which way the rotor should be mounted on the vehicle. The interior vanes of our rotors have a unique vane design that provides air flow through the hat and has the optimum cooling performance. The exterior vanes should follow an exit path to expel the gasses between the brake pad and the rotor to flow out of the rotor to avoid glazing the brake pad.
Q: Won't bigger caliper pistons stop better?
A: While it may seem like "bigger is better," it is generally not the case. Bigger caliper pistons will provide more clamping force but can also have a negative affect on braking performance. If the piston sizes are too large for a vehicle, the braking balance of the vehicle will be upset and braking distances can decrease as a result. Improper braking system balance will cause one end of the vehicle (front vs. rear) to lock up prior to the other, which decreases stopping distances. What is more important in decreasing stopping distances are the compound of the brake pad, usually determined by the coefficient of friction as well as the tire compound. The brake system will only stop the wheels, but the tires stop the vehicle.
Q: Fixed vs. Floating Rotor Systems
A: All metals "grow" when heated. The diameter of gray iron brake discs can increase as much as 2mm (0.080 inch) at elevated braking temperatures. When the disc is radially restrained from growing (as in all one-piece discs or solidly bolted 2-piece assemblies) the friction plates are forced into a cone shape as temperature increases, adversely effecting both temperature and pressure distribution within the pads and the feel of the pedal. The Megan Racing high performance rotors of the GT-200 are mounted on separate billet aluminum hats. The hardware between the rotor and hat is designed to allow radial growth and minimal axial float resulting in a mechanically stable system.
Q: Is it better to remove the Dust Shield/Splash Guard?
A: Depending on the application, the splash guard (also referred to as a dust shield) may need to be trimmed or removed in order to install a bigger brake upgrade. The dust shield/splash guard is typically made of stamped sheet metal and is designed to keep debris out from the inside of the rotor and water from splashing directly on the inner rotor face. Both functions are beneficial on a street car, however on a track driven vehicle, the dust shields may actually hamper brake performance by impeding air flow to the rotor. Practically any debris that can get to the inside of a rotor can typically also get out. If it is not necessary to remove the shields for the installation of a brake kit, you might consider doing so anyway to help cooling. Often times, the dust shield/splash guard is usually modified to incorporate a brake cooling duct, helping route air from the front of the vehicle directly to the inside of the rotor where it will have the most cooling effect.
Q: What pad will work best for both street and track?
A: There is no single clear-cut answer to this question as using a pad for either will be a compromise when used for the other. There is no single pad that will work “best” in both environments. Both environments are uniquely different and require different pad characteristics from the brake pad. There will always be a compromise in one area of operation. Pads are asked to do a number of different tasks in different situations. A good street pad would have good initial bite, meaning it will have some stopping power even when the brake pad is still near ambient temperature. The “initial bite” is important for a street driven car when the pads rarely reach higher temperatures. However, brake pads with good “initial bite” will usually reach their threshold temperature very quickly when used on the track. We never recommend using a street pad at the track. There are a few areas to consider when choosing a brake pad. When you understand the variables, you will be better able to select the correct brake pad for your application:
1. COLD STOPPING PERFORMANCE. How well does the pad grip on the first stop when the system is at ambient temperature?
If you must run one pad on both the street and the track, you will have to compromise performance in one way or another on all the above. We suggest changing to a track worthy pad for track events, with a proper bed-in before the event. The system will need to be bedded-in again when the street pads are re-installed. See the FAQ covering "What do you mean by uneven pad deposition" for more information on bedding pads.
Q: How do I retract the caliper pistons to change pads?
A: As brake pads wear, the caliper pistons extend from the body of the caliper but only retract a few thousandths of an inch so the pads stay close to the rotor face. When installing new pads, the pistons need to be pushed back into the caliper body. This can be done in several ways and does not necessarily require special tools. With any method of pad retraction, be careful not to nick the face of the aluminum piston where it contacts the backing plate of the pad. First off, the rotor is typically loose on the hub with the wheel removed. By rocking the rotor back and forth it will push back the pistons enough to make removing the used pads easier. This is especially true if rotor wear is such that there is a raised ridge on the outer edge of the rotor face keeping the pad from easily coming out the top of the caliper. Our most convenient method to fully retract the pistons is to use the used pads being removed from the caliper as a lever. Remove one pad from the caliper while leaving the other used pad in place. Turn the pad 90 degrees and re-insert half way it into the caliper lengthwise with the pad face still toward the rotor. Using the outer edge of the rotor against the center of the pad, use the pad as a lever to press both pistons in at the same time. Retract both pistons at the same time, or the one not being pushed in will extend further. Push the pads in as far as possible, remove the used pad and install the new pad. Repeat on the other side of the caliper. In retracting the first pair of pistons, the opposite pair of pistons where the other used pad is may extend, pressing the pad against the rotor. Rock the rotor again to move the pad away again. You can also use alternate tools to push in the pistons. I have also used the plastic coated handles on a pair of pliers or channel locks, which allow me to press both pistons at the same time and not nick the piston face. There are special tools available to retract the pistons, however unless you are a professional crew person making a hot swap in the middle of a race, it is likely not necessary. If you have trouble retracting the pistons, you can crack open one of the bleed screws with a hose leading to a tray or bottle and it will ease the resistance. You will need to bleed the system if you open the bleed screw. Also, keep an eye on the brake fluid level in the master cylinder reservoir. You might want to remove the cap on the brake master cylinder to help relieve some pressure from retracting the caliper pistons. If the system was bled and topped off when the pads were worn, you might push enough fluid back through the system to overflow the master cylinder. Be careful of this as brake fluid can potentially damage paint in the engine bay.
Q: What is "uneven pad deposition?"
A: By “uneven pad deposition,” we are referring to the chemical gasses that are released by the brake pads and deposited to the surface of the rotor to create a binding chemical compound between the rotor face as well as the brake pad. The brake pad bed-in process between a brand new rotor surface and a brand new brake pad surface is critical for optimizing braking performance. Improper bed-in process will cause the brake system to perform at subpar levels, below the components' true capabilities. All modern brake pads are what are referred to as an Adherent type of pad, which is designed to transfer a layer of pad material onto the rotor surface. When a sufficient and more importantly an EVEN layer of pad material is deposited to the rotor face, the pad material on the rotor, interacting with the similar material on the brake pad itself, creates the most efficient friction mechanism. These like materials, breaking against each other on a molecular level are what really stops a car well. To emphasize, there must be a layer of pad material deposited onto the rotor surface. The problems occur if the pads are not properly bedded-in with an even layer of pad material on the rotor and the brake system is run aggressively, OR if the pads are overheated (which happens when brake pads are run in excess of their operating temperature range). The pad transfer occurs most efficiently at the pad's optimal operating temperature. A higher temperature pad needs to be hotter to properly and sufficiently transfer material onto the rotor surface. If you have a high performance brake pad and never run it hot enough to get a proper layer or pad material onto the rotor, it will never be properly bedded-in. Thus, even after 1000 miles of "normal" street driving, when you blast your favorite canyon and heat the brakes, you can get uneven deposits on the rotor causing a vibration. The other common scenario is over-heating the pads even if they are properly bedded-in. In this case, the pad material starts to break down and smear onto the rotor face, again causing the UN-EVEN deposits. The other problem that occurs is if the system is really hot and you come to a complete stop and leave your foot on the brake pedal. This causes "pad imprinting" where a small layer of material breaks off the surface of the pad and literally can be seen as an imprint of the pad on the rotor face. This can occur no matter the state of bed-in. All of these scenarios leave very small, uneven layers of material on the rotor. The best way to avoid these problems is proper bed-in of the system initially, and using the proper pads for your exact driving conditions. If you are planning on swapping pads for a track day, you need to re-bed the system before the event (or dedicate the first track session to brake pad bed-in). Remember, you have that layer of street pad material adhered to the rotor face, and if you don't remove and replace it with the track pad material, it is going to degrade from the heat, and cause uneven pad deposits. Same goes when you put the street pads back in, you need to re-bed them for optimal street performance.
Q: Can a dealership deny my warranty claim if I install a Megan Racing big brake system?
A: Information provided in this FAQ provided by SEMA.org.
Federal Warranty Laws
The Magnuson-Moss Warranty Act (15 U.S.C. 2302(C)): This federal law regulates warranties for the protection of consumers. The essence of this law concerning aftermarket auto parts is that a vehicle manufacturer may not condition a written or implied warranty on the consumers using parts or services which are identified by brand, trade, or corporate name (such as the vehicle makers brand) unless the parts or service are provided free of charge. The law means that the use of an aftermarket part alone is not cause for denying the warranty. However, the law's protection does not extend to aftermarket parts in situations where such parts actually caused the damage being claimed under the warranty. Further, consumers are advised to be aware of any specific terms or conditions stated in the warranty which may result in its being voided. The law states in relevant part:
“No warrantor of a consumer product may condition his written or implied warranty of such product on the consumers using, in connection with such product, any article or service (other than article or service provided without charge under the terms of the warranty) which is identified by brand, trade or corporate name....” (15 U.S.C. 2302(C)).
Q: Will Megan Racing brake lines work on my car?
A: Our stainless steel, coated brake lines are vehicle specific and are designed as direct replacement parts for stock brake lines. The replacement lines typically follow the same routing as the stock brake lines. While the design is tolerant of slight modifications to the intended vehicle, any excessive lowering or raising of the vehicle ride height may make the lines unsuitable for use on that particular car, truck, or SUV. Also, the lines include provisions for routing attachments on the stock suspension, such as brackets on the strut. If an aftermarket suspension is used on the vehicle, the stock mounting points may not be present on those components. If alternate routing or modifications are required, it is the sole responsibility of the installer to assure that the lines are not binding or touching any part of the suspension or drive train. Inspect the line routing through the entire range of suspension travel, both up and down and left to right. If there is any question as to whether or not the install is correct, do not drive the vehicle until there is absolute assurance the lines are safely routed.
Q: What are the friction coefficients for the brake pads that you offer?
A: The "BLUE" Spec Brake pads have an operating range of 50 degrees C to 500 degrees C (122 degrees F to 932 degrees F) with a friction coefficient of 0.41. The "SILVER" brake pads have an operating range of 50 degrees Celcius to 650 degrees Celcius and have a friction coefficient of 0.46.
Q: Why don’t you offer drilled rotors?
A: Although most people like the aesthetic appeal of drilled rotors, drilling the rotors takes away from the surface area of the rotor which takes away from the contact-patch that is developed between the rotor and the pad. The holes also compromise the rotors construction and can lead to warping and/or cracking. In general, less rotor material degrades heat dissipation capabilities of the rotor, which is what leads to overheating rotors. Overheated rotors will warp and will become unusable. Megan Racing will always choose performance and reliability over aesthetics.
Q: Is the Megan Racing braking system compatible with Anti-Lock Brakes?
A: Yes, the caliper and rotors often are not involved with the ABS system. Common applications will have the ABS Sensor on the knuckle of the vehicle and a pickup point in the axle or wheel bearing. With the ABS system in functioning order, it will still be operative even with the big brake kit upgrade. It is good to keep in mind that the ABS system is only activated when the wheel/tire locks up on a corner-- the ABS system then restricts the fluid reaching that particular corner to keep that corner from locking up so as to stop the vehicle.
Q: What’s the benefit to a two-piece rotor?
A: The Two-Piece rotors that are on the GT-200 system are designed to withstand higher temperatures than a single-piece rotor. The mating connection between the hat and rotor are designed to allow the rotor to expand under high-heat conditions for extended periods of time. Metal expansion is not uncommon when exposed to extreme temperatures, especially within the brake system. The benefit of our 2-piece floating rotor design is that it allows the hat to separate from the rotor to isolate the heat expansion. When the friction face reaches the high temperature, the bolts along the diameter of the hat will move and release the stress of heat expansion. These temperatures are never seen during street driving and are very rarely seen on drift events and smaller venues, but are typical during high speed road course layouts that are demanding on the braking system.
19481 San Jose Ave
City of Industry, CA 91748 USA
+1 (626) 581-0988
+1 (909) 345-7936
+1 (909) 345-7933
Mon - Fri / 9:00AM - 6:00PM