jrgordonsenior

FWIW I run my 99' with OEM hubs, uprights, and of course brakes. I use cup LCA's, motons, 550/700 springs, Tarett rear toe arms, and GT3 monoballs. I'm setup at 95mm front (cups 85mm), and 115mm rear (cups 120mm). It handles as well if not better than most 6-cups probably because I'm 125lbs lighter. No bumpsteer components and no bumpsteer issues that I can feel....

utkinpol

but you also got pretty much cup car aero too. My car sits imho at 115mm now, or even higher as it has almost 1.5" gap between top of front tire and edge of stock front fender on a similar suspension setup and I was told my my mechanic that I cannot go any lower as it will compromise proper angle between front arms and it will ruin performance and to be able to drop safely any lower to race car height I need to swap hubs and uprights to change overall geometry. may be it is something 997 C2 specific, I do not really have enough details to understand why.
Or was it all BS pretty much?

PS. I just spoke with 2 local pro shops about this - here is simplified version of what I was told.
1. lowering center of gravity does not automatically result in the better grip.
2. Fron LCAs must be as close to parallel to the ground and rear toe arms must be parallel to ground, not jerked up. Even with my 600/700 springs suspension travel is the issue #1 and simple answer for 600/700 springs was that car cannot be set lower than 100mm as if it is set lower than that it will for sure run out of travel at bumps and this is very bad. rear bump steer toe arms are a must too, even with my moderate drop as they are not parallel now.
3. to drop car to cup car height you need LCAs to angle as on a cup - for street car it requires mods to front crossmember to sit lower, possible change to uprights, and much stiffer spring to limit suspension travel so you ride on tires instead of springs and that relates to series of some other changes = an another $10K+ job.
4. everybody, to say mildly, completely disapproved an idea of having nt01 fronts and RA1 rears for tires.

wanna911

I think you have to look at things in a few different lights.

#1 Shops will tell you things so that you don't go out and have an accident/problems and blame it on them (image preservation)
#2 Many shops also base some things on racing which may or may not be directly applicable to street cars driven below the limit for 20-30 minute sessions

I'm not into spending all of the money on cup uprights, it will be beneficial, but probably not unless you are a pro team with a pro drivers and setup to take advantage of it. As for geometry, you can work around much of that. 996 TT is said to have some of the worst uprights and I heard that whole spill several times, yet, took it to Goldcrest and they slammed the car to the ground and told me to have at it. We ONLY raised it back up because my splitter was scraping under the compression in turn 12 at Road Atlanta (but only a little) My tire wear is freaking awesome, 20+ heat cycles on A6's and just did a lap .4 off my best on one of them mixed with 3 other 15+HC A6's. Without some mistakes could have got a PB on old tires.

IMO when you have 5-6 guys running NT-01 fronts and RA1 rears, and FAST, I wouldn't care what the shop says. They know a lot more than we do, but they likely haven't tested that specifically and found an actual problem with it.

Keep your Toe Arms parallel with your lower control arms and you should be ok.

utkinpol

that was exactly what I assumed before, but, now after all those talks it is kinda murky.

i will get back to this issue closer to the weekend.