I have a set of pss9's, and I feel they are too undersprung for track use. I am looking to increase the spring rates by roughly 10% without revalving. I need to keep in mind that I spend more time on the street than on the track.

The original rates are 430lb front 460lb in rear. Thus the fronts are softer than rears, just like oem spring rates.

There is a thread here with a list of aftermarket spring rates, replacement springs follow the same softer front but aftermarket coilovers follow a softer rear rate.

Does anyone here have real experience on the track with their spring rates and care to share their numbers and thoughts?

Thanks

 

I run 650 rear and 500 front on a 2900lb evo. Alittle stiff for the street but the ohlins with stock valving handle them well.
http://www.marshallspec.com/pics/MF1A5244.JPG
On the track I think they could be stiffer, or have some work done on the valving.

 

MMoranda, do you have a stock sway bar with the 650 rear spring rate?

 

I tryed the stock bar after having a works bar but changed to a hotchkiss after realizing the stock was too soft.

 

I've started with 571/457 at the beginning of 2006 and have tried the following:
571/500
500/500
457/500

571/457 and 571/500 both understeered everywhere. 500/500 felt quite good but it still had a bit of push. 457/500 leaves a little bit of understeer for the street but I can tune most of that out by setting the 25mm solid rear bar to the medium setting.

571/500 was too stiff for the street. 500/500 was reasonable for the street and 457/500 feels quite tolerable. A better track setup would 500/571 but I don't know if I want to run that stiff on the street. I was getting good tire temps with 500/500 and 2.5deg front camber. With 457 rates I need a bit more front camber.

My car is an '05 RS and I've removed 15lbs unsprung mass (wheels+RacingBrake BBK) off each front corner and another 20lbs by using a lightweight battery.

Edit: tire temps and camber settings are for Toyo RA1s.

 

Very interesting info redvolution, thanks. What dampers are these being used with?

 

I think you need to set some goals for the new spring rates that can be measured quantively instead of through feel.

I'm not doubting you need a different spring setup, but before picking rates, figure out why you need new rates, then pick 'em.

Just trying to save you some time and money.

Although, it looks like redvolution has given some good data feedback for you to use.

 

New-gen Ohlins R&Ts revalved to the Gerrard/Vishnu spec - they are superb.

 

InSlow,
I have PSS9's but use them for autocross. Coming from a very reliable source, he said that you can run upto 600 lb spring rates before you need to revalve. On a negative side, you will lose some of the soft adjustment settings at that spring rate. I was thinking about having mine revalved by Bilstein (@ $125 per side), but decided to move on to a 2-way adjustable coil-over. Good luck.

Dennis

 

Nice! Glad to hear that these are living up to expectations. Thanks...