Ground Control Koni Performance

[Racecomp Engineering]

The issue here is the shocks. It's not impossible to get those spring rates to ride relatively comfortably, but clearly the valving is not working out for you with your set up. Also, the rear adjustment method is needlessly complicated.

I don't think you're going to get the ride/performance compromise you're looking for without different valving, and I'm not sure I would bother revalving what you have now.

- Andrew

[thebutterson]

Have you seen this series of videos?

https://www.youtube.com/playlist?lis...C286CD2172A755

I've been watching those and reading "How to make your car handle" as well as the "Autocross to win" site. I'm pretty new to suspension tuning, but I'm familiar with the ride quality you're talking about. I have an E36 318ti with a set of GC coilover conversion springs and adjustors on otherwise stock koni SA's and have the same ride as you. If I back off the rebound adjustment the car bounces wildly, so to control that I have to increase it, but then its still not soaking up the bumps.

From what I've read, that poor ride quality is due to a combination of things a lot of companies do when selling an off the shelf setup.
- Much more rebound than compression which pulls the suspension down onto the bump stops
- Linear damping that doesn't blow off in the high speed range to allow you to soak up bumps
- Lack of travel when lowered - although I think GC and many others use a shorter shock if you buy a setup meant for a lower ride height

If you're happy with the way the springs control the motion of the car you could call GC and see if they can help you spec some sort of double digressive valve curve that will provide more compression and blow off more in the high speed range for comfort. I don't have first hand experience with this, but its what researching the above sources suggests is necessary for a well controlled setup.