borowiec

I use my 1975 911S primarily for autocross but it still needs to be driveable on the highway, so I can get to the ax events, some of which are 4 hours away. The car is currently all stock but I plan to upgrade the suspension this spring (adjustable shocks, turbo tie rods, bushings, adjustable spring plates, etc.). I'll be putting 21mm torsion bars on the front, which seems to be the consensus among the dozens of people I've asked about this. However, I can't figure out what size torsion bars to put on the rear. Bruce Anderson's book says 26 or 27 mm, my mechanic says the same thing. Well, which should it be, 26 or 27? Driving other 911s to see the difference is not an option, since everyone I know has later cars that are much heavier, such as the SC. My car has no a/c, no power anything, no stereo even, so it's quite light.

Any suggestions would be most welcome!

Andrew Borowiec

75 911S Targa, future AX car
88 Carrera coupe
02 Saab 9-5 Linear wagon
01 Audi A4 Quattro (the wife's car)

JackOlsen

Even with 27mm bars, you'll be fine, in terms of ride comfort. I thing you'd be happy with it all the way up to as much as a 22/29 combo.

Peter Zimmermann

Andrew: I agree with Jack about the T-bars, but I also want to touch on another part of your post. Why would you want adjustable shocks? In my view you would be better served using Bilstein HD shocks revalved for semi-performance use. I've always felt that the fewer things you have to adjust the easier it is to set up the car. I've won a lot of competition events, and, except for my SCCA E/P car, I've never used adjustable shocks. I don't think that decision was flawed and I can't think of a single event that adjustable shocks might have earned me another trophy. I'm no M. Schumacher - not even close - and I can't feel a .25 pound change in tire pressure, so why have shocks that might require changing? Just my two cents worth...
Pete

JackOlsen

I agree with Peter. Adjustable shocks are pretty much overkill for anything less than a dedicated track car with a suspension expert doing the setup.

borowiec

Regarding adjuctable shocks, everyone I have talked to, including my mechanic and other autocrossers in the local PCA, recommends Konis, the idea being to adjust them as stiff as possible for autocross and then tone them down for everyday driving. I'll have to ask around about Bilsteins.

Andrew