Alex, you have to be careful in what you wish for. There is a reason that even race cars today still have moving suspension. Make it too stiff, and the car will be skittish.

 

good point Mike -
Any rule of thumb on how stiff to go? I know people are adding the TRGs to their cars. Anything special being done to overcome the possibility of "skittishness"? I don't mind a firm ride and am willing to exchange some extra comfort for performance (can I help it? I am hooked!!!!!!!!!)

 

so true.. my car is now ultra sensitive.. and I wouldn't want it for a street driver.. AND I wouldn't want it as a beginner.. it is so sensitive now! ...not as forgiving... you better be a pretty good driver before you go too stiff (too sensitive) IMHO anyway... FWIW

 

I think it's a fairly delicate balance between the spring rates and the sway bars. I don't know 993s well enough to give any sort of advice on suspension setup, that's why I ask Viken and others who do. I can give all the advice in the world on a Miata :-)

Essentially, you do want the car to lean some in order to make tires work and help you turn in and then hold the turn with outside rear tire. TRG bars, altough adjustable, appear to be better mated to stiffer springs, to my taste. Than again, how much the car spends on the street, how rough the driving surfaces are and a few other determining factors come into play.

 

Mike,
I just upgraded my US MO30 to the 21 rear bar. With the 21 front, the change from the 20mm rear was really noticable. I really love the setup. I have H&R springs on worn out US M030 shocks, with a Pss-9 set sitting in my garage. I thought that I wouldn't feel a 1mm difference, but someone on the board did the math and illustrated that in my case, a 1mm change equated to nearly a 30% increase in stiffness for the rear bar.

 

Tom, I realize that increase is significant, I'm just beginning to worry about snap oversteer near the limit with such a thick rear bar.

 

Mike - It is darn near impossible to have snap oversteer in these cars. Porsche has done a great job to keep them very stable. Does that mean that if you are on the limit in a hard turn and lift that the rear end will come out? Yep, but that is not a function of the sway bars....

 

Thanks, Bob!
I am waiting to excercise a 993 (or a 964, not sure yet) at a two-day event this weekend to understand how it behaves. I put 16K miles in 8 months on my street 993 and still have not figured out how it handles - the suspension is shot and I'm not stupid enough to go look for limits on public roads.
So, I'll have a better idea after the weekend.

 

Hi Mike,

I ran my car with the high-boy ride height and worn boingers (with 22mm/20mm sways) on the track for almost 3 years. While clearly not the optimal setup, I learned to focus more on me and enhancing my skills and technique, and just let the bouncy/floaty car "do its thing." Now with PSS9s and a 21mm rear bar, sure my times improved, but I feel the greater improvement is in the area of ride quality and inspiring more confidence. If you're already an "autocross junkie," then you'll be fine with whatever; just have loads of fun! Take care.

Edward

 

It took me a while to get used to the thicker bar. I drove the car in a nasty Seattle rain right after installation and boy did I get the tail out! This was clearly a function of me being an inexperienced driver... after a couple of days I was really enjoying the "flatness" of the tail end. Before the mod, with the 20mm, the rear end would lean much more. The difference now is significant and I really am enjoying it. Best of luck with your decision!

 

I have the H&R springs, Bilstein HD's and RoW Turbo bars (thicker in rear than US Turbo) with 225/45/17 and 255/40/17 on stock Cups - great balanced setup without being too pricey. Handles much more like an early 911 (but more benign) than the understeering setup that comes with the car!