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Nov. 14, 2011 2:54 p.m. wbjones SuperDork

I'm planning on running TT with NASA next yr and tire selection is the question

if I want to use the R6's or others of like stickyness it will cost me 10 pts in the classification section ( can't afford 10 pts)

so the question becomes ... which of the " autocross" type tires would make the best track tire ( will usually be used in 85 - 100° air temps with correspondingly higher track temps )

these are the choices ( I run the R1R's for autocross )

Toyo R1R,
Dunlop Direzza Sport Z1 Star Spec
Bridgestone Potenza RE070 (not familiar with this one ) (better/worse than the RE-11 ?)
Kumho Ecsta XS
Yokohama Advan A046 & Neova AD08
Hankook R-S3)
Nov. 14, 2011 2:55 p.m. mndsm SuperDork

I'd go *specs or RS-3's.
Nov. 14, 2011 2:56 p.m. Javelin SuperDork

RS-3's
Nov. 14, 2011 2:56 p.m. 92CelicaHalfTrac SuperDork

RS-3
Nov. 14, 2011 3:00 p.m. stumpmj Dork

Can you remove some other mod to be able to run the stickies? I can't think of anything that would make you faster than Hoosiers.
Nov. 14, 2011 3:08 p.m. ST_ZX2 Reader

Kumho XS like heat. A lot. Just don't try them in rain.

I run Dunlops, they are good all-around, but do fall off a bit when really hot.

Here is what Andy Hollis had to say--

"IMO, your best bet will either be the Kumho XS or Hankook R-S3. Both are very fast and neither is the wrong answer. It will come down to sizing and balance. The XS will tolerate the heat a little bit better, but also needs way more heat to work. This works well on a balanced car like a Miata, BMW, or RX8. But on something like a FWD CRX, there isn't enough weight in the rear to keep the grip level the same front-to-rear.

The R-S3 is faster out of the box and never really loses all that much until you really work them hard on a hot day. It also has the magical 225/45-15 size, which is key on a number of smaller cars.

On my Civic and CRX track cars, I personally run the R-S3 all around for most of the year, though I'll put some Falken RT-615K's or Toyo R1R's on the rear for cooler winter days to keep the relative balance in check. For hot summer days and full 20-minute sessions, I run the R-S3 on the rear only, and the XS on the front. That combo is fast and consistent.

The Dunlop is a great tire, but slower, IMO. The first lap is typically the best, and then it falls off somewhat. Once it does that, though, it stays consistent for the rest of the session. And they have the largest sizing selection. That's key to its popularity. Oh yeah, and among the three, the Dunlop is way better in the rain. So for a double-duty daily-driver, it's a good choice."

--Andy
Nov. 14, 2011 3:45 p.m. wbjones SuperDork

stumpmj wrote:

Can you remove some other mod to be able to run the stickies? I can't think of anything that would make you faster than Hoosiers.

not really ... shocks/springs/rear bar = 7 pts ( car starts w/ 7pt penalty ) = 14

these are the tire "penalties" was going to run the Hankook Z214 (C51's) but that's 10 pts... Hoosier as you see =13

either of those moves me into TTE... would love to stay in TTF... I've run competitive times on R888's but they're +7... figured I'd need to stay in the + 2 category ... oh and the 225's would be +1... ( 215 is the base size for TTF)

what I really wish is that any of these came in a 225 - 45 - 13 ... the affect on overall gearing on the CRX is amazing

A. TIRES: 1) The following DOT-approved R-compound tires: Hankook Z214 (C90 & C91 compounds only), Hoosier A6 +13 2) DOT-approved R-compound tires with a UTQG treadwear rating of 40 or less (examples: BFG R1, Goodyear Eagle RS, Hankook Z214 (C71, C70, C51, C50), Hoosier R6, Kumho V710, etc. --note: Grand Am Continental & VRL Hoosiers OK) +10 3) DOT-approved R-compound tires with a UTQG treadwear rating of 50 to 130 (ex. Kumho V700, Michelin Pilot Sport Cup, Nitto NT01, Pirelli PZero Corsa, Toyo R888, Toyo RA-1, Yokahama A048, etc) +7

4) DOT-approved (non-R-compound) tires with a UTQG treadwear rating of 120-200 (examples: Toyo R1R, Dunlop Direzza Sport Z1 Star Spec, Bridgestone Potenza RE070, Kumho Ecsta XS, Yokohama Advan A046 & Neova AD08, Hankook R-S3) +2
Nov. 15, 2011 3:59 p.m. wbjones SuperDork

that answered... now... assuming I'm smart enough to take Andy's advice ( I've never run either Kumho XS or Hankook R-S3 ) what ball park hot pressures should I look for (hot)

CRX w/ 3 1/2° neg camber front (yeah I know that's a tad more than I need) and 1 1/2° neg camber rear..( the pyrometer said I was "ok" on the fronts and nearly perfect on the rears this weekend at NCCAR (RE-11's)

450# front and 400# rear w/22mm rear bar set full stiff

any suggestions ?