Coilover Spring Rate Recommendations?

[jonnyd330]

I am about to order coilovers for my sedan, I am pretty seriously looking that the ISC Suspension setup in a street/sport valve. http://iscsuspension-na.com/store/#!/BMW-3-Series-320-330-00-05-E46-ISC-Adjustable-Coilover-Car-Suspension/p/28352629/category=12617115

They load those with 8k front and 10k rear. I know from some other threads the most common spring rates tend to be 8k front and 12k rear. Just wanted to get some opinons on what I should do. I figure if I really don't like the rates at first I can always get some swift springs down the road.

The track/race valving option comes with 10k front and 12k rear.

Thoughts???

[slater]

to maintain factory suspension frequency, i would go 7k/12k. if you stray from that balance you'll create a lot of pitch (and understeer if you go to high on the front).

[nsk040]

12k sounds very high to me. Here's a link (at bottom) talking about 450lb at the rear on a track car w/ sticky tires - this equates to ~8k.

Stiffening up a car will make the car feel more responsive, but it won't necessarily improve the handling, and could actually make the car worse. The springs and shocks need to be matched, so if you don't like the spring rates you may not be able to change them much without hurting the shock performance. Everything also needs to be configured properly with bars, alignment, ride height, corner weights, etc. not to mention the damping adjustment that your linked product offers. While it is more expensive, it may be worth going with a more reputable product that has been tested extensively and is sold by a vendor that can help you dial-in setup.

http://www.vorshlag.com/forums/showthread.php?t=8448