I have a set of coilovers that I am having built at ground control. I need to pick the front and rear spring rates. My choices for the front are: 350, 375, 400 and the rear can go 340, 380, 440.

I was thinking of a 400F/340R rate. Currently, it's at 375F/250R.

 

400/340 would be my choice out of those rates.

anything else has the front rear rates very close to each other, or the rear higher than the front... seems like a recipe for a tail happy car, all other things being equal.

 

yeah, i just figured that if it turned too tail happy at 400/340 then i could just remove the rear sway bar.

 

I have 385 front and 300 rears. I got the softest rates for the size springs I ordered, once I track the car and learn it, then I'll play around with springrates if need be.

 

Just remembered that the rears are stock valved koni yellows. Is it safe to move up to a 340lb spring on those shocks?

 

400-340 should work nicely w a dual purpose street/track function. just remember to run 2 to 3 psi less in the rear. your konis will work fine...

25 inch ride height front and rear.

good luck,

howard coleman

 

^^^

Honestly, not to argue with Howard, but I'd go higher w/ Konis... it'll actually HELP your ride quality. When I had Eibach pro-kits, with are about 365/285 (IIRC), the thing was always crashing down over bumps and such. My GC's are 500/400 and it's actually much better, particularly if you're going to run as low as 25" like I do and Howard suggests.

You'll find that the shock valving has more to do with ride quality than spring rate (within reason) anyway.

 

yeah, i think i'm going 400/340 and running the rears at full stiff (dyno matched of course)

 

FWIW I'm running this setup with 450F/350R, 25" ride height, and I'm pretty happy with it.

 

SA/FB or FC or FD, what car are these for? Looks like an FC in your pic, but I think you are getting "FD advice".

-Max

 

Woops, sorry, i never specified. It's an FC. Pretty much, the information that I've gathered from multiple forums states that the konis should hold up with a bit of compensation on the damping setting at 340lb. The fronts will be going with 380-400.