I'm looking forward to next seasons track events, and am planning tire replacements. I have run 7 track days on original S02s, and the rears won't last much longer (about 9000 miles total on them now). My car is stock other than pads and fluid, and will likely stay that way. I don't have an extra set of rims to dedicate to track rubber (I'm a tightwad), so I'm considering replacing the S02s with R-compound and drive them on the street. My question is, are R-compounds dramatically better than S02s for track days (I don't autocross, only DE and open track roadcourse events). I'm considering Michelin PSC in 205 and 245, or maybe the A032R. If I put $1000 of R-compound tires on and can't tell a substantial difference I'll be disappointed. I can replace the rear S02s for $400 and just continue to use them.

 

I would use RA-1s for street/HPDE use. PSCs are $$$

You will definitely feel the difference.

One note of caution: When R compounds reach their limit - it's pretty sudden - and you don't have a lot of squealing for feedback.

You'll also get plenty of advice re: shaving as well. Run them on the street for a few thousand miles first or else get them lightly shaved before you hit the track.

 

The PSCs take a very long time to warm up and are not ideal tires for short HPDE events. As lig said, you do not want to run full tread RA-1s on a dry track. My first set was shaved 4/32nds and they were still scary as hell under braking. VictoRacers are also an option, but they'll heat cycle out very quickly, especially on the street.

 

Oh yeah, the biggest difference you'll notice to S02s is your times dropping by 2-6 seconds a lap. There are a lot of corners I could take flat-out on S02s that I can't on RA1s, mostly due to the higher speeds. Don't let that fool you, though, cause you're still much faster in the end.

 

We will be too, because there will be a significant change and you should be clearly faster...

 

R-compounds are not intended to be driven on the street. If it happens to rain you better drive very very slow so not to hydroplane as the R-tires have little to no tread. Also, the R tire's heat cycle life will reduce dramatically. These tires life span are based upon heat cycles not tread depth, even though if you see cord the tire is toast.

 

RA 1s withstand heat cycling very well. I don't drive my Victos on the street but am leaning towards RA1s for my next set of street tires.

The S2000 isn't my daily driver so it doesn't see much rain - but RA1s with tread are o.k. - not great but acceptable.

I can't convince the wifey that I need three sets of wheels/tires just yet.

 

I went through this same decision when I bought my last set of new tires. An alternative for you to consider: I run Khumo MX's on both the street and track. Given the distances here in the PacNW and the difficulty of GETTING extra tires/wheels to the track, it's just not worth it to me to try to run race tires, and I find them a reasonable compromise for both applications. They're better in the rain than RA-1s and better at the track than S-02s, but I can't give you any hard data about laptimes. Just my gut sense that they're faster. And they're reasonably cheap!

 

Chris - everyone seems to love the MX. I'm interested in the new Azenis Sport as well. They are supposed to be out in lots of S2000 friendly sizes soon.

 

Thanks for the good info. I havn't considered Kuhmo MX because they aren't available in 245/45/16 according to tirerack. Do you run 225/50/16 in the rear? Is the size equivalent? Also, I'm confused by the specs on the MX - it is a semi-competition tire, but not R compound and has a 220 treadwear.

TireRack.com shows only PSC and A032R as options if I stay with 205/55/16 and 245/45/16. The A032R seems interesting, as I can get all 4 tires for $675. They seem to get mixed reviews though. Jim@tirerack says PSC is the most streetable R-compound and the only one he might suggest for street/track duty, but they are darn expensive.

EDIT: Since it seems that everyone agrees that any R-compound is dramatically better than S02s, I'm leaning toward the A032R or RA1, unshaved. Should I buy them heat cycled first? What is your opinion of Yoko A032R-H vs RA1? My S very rarely sees rain, so I'm really only interested in how they will perform on the dry track. These tires will be driven on the street though, and to/from track events.