If you really just want to "stance" your car, you need to go here: https://www.evolutionm.net/forums/evo-show-shine-86/

If you really want to tune your car's suspension for performance, you need to read everything posted and linked to here: https://www.evolutionm.net/forums/ev...ead-links.html

...and if you're just trolling ... well...

l8r)

 

Im about to get some wheels and coilover for my evo 8, can someone give me some advice of what to get? Since i dont have the time and money to play around, i thought i would ask someone here on this matter. I going to buy Varrsteon wheels 18x9.5 with 12 offset. What would be the best coilover for it? Give me some names and price on each if u can. And if u can tell me the spring rate that u can recommend me on it too..... Thanks

 

See above

 

Just read all 23 pages. Great thread and very informative especially on how things apply to the ct9a. Thanks guys.

 

I recently measured, weighed, and built a template for the suspension on my racecar to prepare a cut-sheet for a custom suspension order. I have a question regarding valving & springs to achieve critical dampening (to double check my work). What is the correct formulae to evaluate critical dampening and specifically what variables go where?

Also, I have a backup set of Muellerized JIC coilovers that I'm planning to benchwarm when I acquire a 2nd set of JRZ's. According to my recent shock dyno plots the valving is way out of spec with the current springs for critical dampening for the chassi I'd like to bolt these on. I don't want to pour too much into them, is it best to just buy springs to match the current valving to optimize them or should I buy springs and rebuild? Is it typically better to select springs based on the inputs and valve to them? Is it possible to work with existing valving and go the other way by selecting springs to match it?

Amazing thread!

 

I would strongly recommend purchasing this book: http://books.sae.org/book-r-146/

It's thick & dense, but it contains answers to all of your questions as well as all of the questions you haven't even considered yet.

However, I would still recommend consulting with the suspension company you're ordering from and letting them choose the initial valving given your measurements & inputs.

What are you going to use these coilovers for? Daily driving or actual racing? If it's daily driving and you don't want to spend much money, I'd leave them as-is. If you're actually racing on them, I wouldn't cut any corners. Pick your spring rate, have them rebuild & revalved. I wouldn't waste any time or money on a compromise solution that you'll probably re-do later anyway.

 

I already read it, and the problems, setup, and solutions addition. It was independent study so no collaboration on correct vs. incorrect. That's why I asked. Might work better if I try posing my question like this instead...

Critical damping Cc = 2 * SQRT( K * W / g ) . . .?

K = spring rate (lb/in)
W = the weight (lb) of the mass that's "vibrating"
g = the acceleration due to gravity (386.4 in/sec^2)

Translation... Critical Damping Constant = C = 2*square-root ((equivalent spring rate) * (equivalent mass))

To determine a 65% critically damped suspension, you need to make the low-speed equivalent damping coefficient Ceq = .65*C?

Apply the suspension motion ratio to convert the wheel rate and valve, right?

 

JFast - that kind of talk is not welcome around these parts. Please keep your suspension discussions to any of the following:

"What is the lowest I can cut my springs on the stock shocks"

"I bought these $800 coilovers to lower my car and now it handles worse than before"

"I lowered my car and now it handles like crap. Do I need an alignment"

"How do I stance my EVO"

"My rimz are hella flush but I get a scraping noise whenever I hit a bump or turn"

 

Hey guys! Great thread, I think I learned a good bit from it. Hopefully you seasoned racers don't mind giving out some more advice:

My car is currently a weekend warrior, mostly taken out on nice days. I'd like to start doing HPDE events as often as possible pending my work schedule. My car currently has Tein H springs up front and Tein S springs in the rear. I am aware this is not an optimal setup, however, they are what came on the car when I bought it.

I am going to do a HPDE as is first so that I can experience how the car performs, see what I like about it, what I don't like, what it's lacking, etc. Improvements will be made from there.

At what point would you consider looking into a coilover setup over struts/springs? With HPDE in mind, would it be beneficial to try a new set of springs after my first run? Would it be a waste? Is there anything you would recommend adding to the car before I even make changes to the current spring setup?

Thank you guys in advance!

 

Awesome post! New springs and valving is ****

 

hey guys I need your opinion on spring rates

I have I really stiff evo 9 ( full solid bushings, weld-on roll cage, seam welded the chassis and a 26mm sway bar) I has two guys that recommended spring rates for me one from race comp engineering Myles Williams told me to go with 12k/16k and the other guy Robi from ROBISPEC told me to go with 10k/11k if your using my sway bar and I am. I told Robi why this low rate he sad that the Evo's are designed for rally you will have more traction if you let the car roll a bit.

also I am running semi slicks tires and of course only track use

need your recommendations

thank you

 

If you do not have a fsb, I would get one before anything else and drive your car to see what's needed. Although I never had one and sold my car before I put one on, in retrospect the fsb is the key suspension component before dialing in the rest of the suspension. This has been posted elsewhere and you can read GRM articles about this. I had everything else and was still slower than others who had fsb. The car can roll, but should not require 4* of camber.

 

it seems evo need ALOT to handle close to perfect. Is this true for other platforms? IE using FSB/RSB, strut bars, top end coilovers? Ive never seen cars tripod as bad as ive seen the evo do it.

 

What kinda stance will get me some b1tches, yo?

 

Can someone help me pick out some spring rates for my car? I auto-x and have two local hillclimbs... Planning on buying some Ohlins DFV's... I have been recommended 10/10 and 10/12. My set up is 17x9.5 RPF1's with 255/40/17 ZII's and a re-stacked stock rear diff. I was thinking about picking up a FSB at the same time and the Cusco mounts if money allows it. My previous suspension was re-valved Bilsteins with swift springs and stock bars.