A911RCR

I have a 1993 RS America with a PSS9 kit on it.
Been happy with the performance on and off the track, yet its still a compromise for the track setup. I'm looking to get closer to a 964 Cup setup.

Has anyone added increased the springs to Cup rates on a PSS9 setup?
I understand Cup Springs to be 450 / 600.

If you have, did you re-valve or go with the stock valving?

Bilstein gave me these numbers for spring rates

964 PSS9 kit.

Front : 225 main / 255 tender
Rear : 405 main / 570 tender

In looking at compression and rebound settings - it seems the PSS9's almost overlap the RS and Cup settings - suggesting springs are the only change needed.

Comp / Rebound:

964 HD (OE)

Front Rear
Reb/Comp Reb/Comp
2230/845 2740/1215



964 PSS9

Front Rear
Reb/Comp Reb/Comp
Soft (9) 2595/1025 2950/1420
Hard (1) 3425/1455 3490/2030



964 RS

Front Rear
Reb/Comp Reb/Comp
2590/840 3200/1670



964 RSR Cup

Front Rear
Reb/Comp Reb/Comp
2200/670 3790/1720

Any input would be appreciated.


Ross

prince12

Sound Good!!!!!!!!

UncleRemus

What units are you using for the compression and rebound and where did you locate them? Damping is a factor of velocity, so I'm wondering if this is one point on the curve where they match up. In any case, I've never seen anybody quote compression and rebound numbers, only charts.

provoste

I'm running a PSS10 with H&R ID race springs 7 kg front (~390 lbs) with 10 kg rear (~560 lbs). I can't compare it to the OEM PSS10's set up since I put stiffer springs on from the start, but it works very well on track.