market comparo: RS vs. Cup?
#31
Nordschleife Master
Join Date: Oct 2004
Location: Vacuuming Cal Speedway
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To run competitive grip in corners any 996/997 should get full cup car suspension pretty much, hubs, uprights, arms. stock geometry in 996/997 base does not allow to drop it way low how cup car sits.
As soon as you got cup car suspension you get all same maintenance.
Costs are all same, only level of ignorance differs.
As soon as you got cup car suspension you get all same maintenance.
Costs are all same, only level of ignorance differs.
#32
Rennlist Member
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....
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.
Last edited by utkinpol; 07-18-2012 at 11:13 AM.
#33
Race Car
Join Date: Apr 2005
Location: With A Manual Transmission
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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.
#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.
#34
Rennlist Member