Here's my latest UOA: On the left, 3 sessions of 20minute track time. The previous is 48 runs of autox. Pretty similar, and overall pretty darn good wear on my motor:

 

If you are running sticker tires, you get away with higher spring rates, to a point. Even Stiffer if you're not trying to be easy on tires. I'm surprised you have so much roll, to be honest.

I used to tripod on my R-S3s, too. 8k front, 9k rear springs.

 

Stock FSB, Whiteline RSB too. Do you have different bars? I'm surprised too.... maybe I'll "need" the springs... the Z1SS don't grip for **** anymore, I won't be surprised with picking up at least 1s from the RE71Rs.

Man your car is sexy! Autox does tend to generate more roll than road racing, I'm actually surprised/impressed you got on 3 wheels there! Not sure what you're running now, but that does tell me you would want more spring, no?

 

** edit: thank you for the compliment! My girlfriend doesn't like the competition. LOL
At that time I was on stock sway bars. I couldn't go with heavier springs without losing grip from the tires. I would have ended up killing them and sliding all over. I had enough roll to keep everything grippy.
I'm now on one of Robi's RSBs, adjustable endlinks f/r, 9k/11k springs, and Bridgestones. I need to drop to 10k in the rear per Rob (and I agree). I may have a pic of how the car turns now. I'll look.

Last event, on current setup:

 

weird how we are having such differing thoughts on the springs.. talking to you, makes me want to stick with 8/10.. everyone else, 10/12 is like a given. If I'm rolling that much with the grip the Z1s generate, I am almost certain to be really tripoding on the RE71Rs... and I really don't want to touch the front bar.. total PITA.

 

Everyone keeps telling me to go 10/12 also, but RobiSpec Tunes some pretty serious cars that do really well. He knows a hell of a lot more than I do, so I told him I would try his way first. So far the car seems to respond pretty well. He told me that since my car feels pretty neutral At 9/11 K, that I should drop down to 8K in the front. In my post above I said he wanted me to drop the rear to 10k. That wasn't correct. He told me to run 8/11 K but keep a set of 10k springs available just in case. Either way, I'm running stiffer than he recommends. This is all based on my coilover and mostly the tire set up. He says anything stiffer is just going to overwork the tires needlessly. He went into tire deflection and how there is no way to dampen the rebound from sidewalls etc. I took notes but no way I can remember it all off the top my head LOL. the guy seriously knows his stuff.

I do know that stiffer springs help the car feel more responsive which makes it feel like it's going faster even if it's not.

I just have to be disciplined enough to ignore popular opinion and trust his judgment LOL

My coilovers are single adjustable AST, if that makes a difference. When I had my KW, he recommended the same spring rates.

If I ever make the move to r- comps, then I would be running considerably heavier spring and possibly a front sway bar. Until then I won't ever touch my front bar.

 

gotcha, good info - to note, is he speaking of road racing specifically or in general?

Still may go 10/12 lol.. We'll see after this weekend

 

You really need to play with the dampers. 6 clicks of adjustments makes my car go from undriveable at an autocross (WAY too much body roll and uncontrollable weight transfer), to point and shoot. I really think you don't have enough damping and should start there.

 

yup, that'll be this weekend. i should get a solid 16-20 runs in, though conditions not yet known. i've been running around 17 clicks from soft (35 clicks total i think) since around April when I had a school/TnT with the car, and was determined that that was roughly a pretty good spot for the car. Will start this weekend with 15/15, and keep moving up as I make notes. Don't think there's going to be a photographer there to shoot pics, but hopefully I will be able to draw some conclusions. All that said, this will be on tires that probably have no more dry grip than a set of all seasons now. Will have to redo this test in the spring with RE71Rs

 

Specifically, road racing. I haven't found an advantage to going stiffer for autox, but I admittedly don't research AX setups. I take my road setup and deal with it for the autox sessions. Otherwise I'd be running 275s on a stock wheel LOL.
I know my 9/11 feels much better than the 8/9 did, but I don't think its any faster (Not sure if slower). If only I had a way to test back to back.

 

gotcha. reading some of the choosing spring rate threads to get a better understanding overall, even if I don't go through with it.

when you say 9/11 feels better than 8/9 what exactly do you mean?

FYI I have ER's ACD tune (actually set milder than most, still rarely use the looser settings) and Cusco 1.5 way shimmed and all by Jon@TRE. Not sure how much impact that has.

Also have the WL front control arm bushings, rear trailing arm bushings, roll center adjuster, and bumpsteer kit, if we're gonna lay out my whole suspension set up and the WL bar set at full soft, which I'm genuinely considering going back to the stock bar.

Also to note, I'm close to a full weight car (~3200lbs), and am corner balanced. IDK if the RE71R is going to be a popular street or track tire due to how extremely fast it wears (200tw.. really?) but for autox people are calling them hoosierstones lol - and that they feel like worn out rcomps. Most of the data I'm seeing is pointing me towards stiffer rates for autox, but again I don't want to if I don't have to, or more specifically if it is going to be slower.

again though, as letsgetitdone has been saying, as far as the body roll goes, will really play with the clickers this weekend. and even after all that, I could be satisfied and then after getting re71rs realize again that I want stiffer rates.

 

Quick rundown of what I have:
Poly bushings on all control arms, rear diff, and sway bars
25mm RSB set on the next-to-softest setting
Perrin PSRS
Home-made adjustable end links
Vorshlag camber plates
re-stacked rear diff


By “feels better” I mean that the car seems to change direction faster, which is to be expected, but I’m on a new tire and coilovers, so I can’t say which has contributed the most. Also, I don’t have data to compare the different spring rates so I’m completely going by feel. I think the Bridgestones are sticky enough that I’m able to get away with the heavier springs, though I can’t say how long the tires will last. I know my Hankooks lasted forever on my 8/9 setup. I did Time Attack, an HPDE, a few AX events, then handed them off to someone who got nearly an entire autox season out of them.

 

gotcha - how much does your car weigh?

 

I have no carpet or back seats (slowly putting the interior back together per GTA Street requirement). Everything else is standard. I was actually taking it it to a scale yesterday, but then it started raining.

 

oh got it - we're probably pretty similar then. pretty standard for me as well.