RL911

I have a stock 1993 968 (w/o M030 sway bar) that I am setting up for the track and street use, probably 8-10 DEs per year. I am going to upgrade the suspension and would like to know what the front and rear coil tension rates should be for this car. My driving skill is intermediate with an eye on the higher run groups. I'll probably be running Koni adjustable shocks in front and rear.

Thanks for the help...

trackdaycareracer

I have a 968 with yellow (1-way adjustable) Konis, stock front springs and stock rear torsion bars (not M030). In addition I have M030 sway bars. Running 235s front and 265s rear semi slick tyres, it is way too soft for track use. Mind you it is still a great car to drive, but it leans a lot during hard cornering and braking. I think you should go with KW Variant 3, which is 2-way adjustable street/track coil-overs with a fixed high-speed compression. A friend running these in his 968 reports that the car is just as comfortable on the street as it was with the stock suspension, but the car hardly leans during cornering - sounds like a good deal! KW will help you with the spring rates before you buy, just tell them the car's intended use. I'd keep the stock torsion bars for safety, but these have to be re-indexed once you add coil-overs in the rear. Please keep in mind that running a set-up like I currently have, with stock springs and stiff sway bars, the sway bars will add stiffness to the front springs. It is also a possibility that the control arms in the area between the sway bars and the coil-overs will crack when the sway bars are stiffer than the M030s.

In general, 968s tend to oversteer more with stickier tyres so some people go with really stiff springs up front to counter this. Finding the right compromise between a bone-jarring trackday car and an acceptable street ride is a challenge! There has to be a correlation between the spring stiffness and the damper, otherwise the car will be over- or underdamped which is not good for the handling. In other words: Should you decide to go with yellow Konis, there's a limit to how stiff you can go before the Konis are overwhelmed by the springs/t-bars (600# ?). Also, without high-speed compression adjustment the ride can become harsh. The short answer: Find some coil-overs that are within your budget and give their tech department a call, I'm sure you'll get the right set-up for your car and intended usage

Crazy Canuck

A buddy has Motons in his car. Oh boy they are sick.

He had the Bilsteins in for one year and got rid of everything for the Motons.

mikey_audiogeek

Great answer!
Mike