ZDan

I've been running Yokohama A052 this year with great results (undefeated in T50 class w COMSCC). 225/40-18 fronts with 255/40-18 rears on factory 18" wheels.
After only 4 track days on these tires (one of in the rain), the fronts are blistered and coming apart at the edge of the tread (yikes!). All clockwise track events, and the left/outside front coming apart on the outside edge, while the right/inside front is coming apart on the INside edge! And I expected to get at least 6 track days out of these tires...

Car/setup info: '11 Cayman base 2.9, only mods are Borla catback exhaust and GT3 front control arms. -3 front -2 rear camber, 0 toe up front, ~0.10-0.15 degrees total rear toe (I forget, but in that range, I don't have alignment sheet in front of me).

NEED a set of tires, and I'm considering a new set of 225/255 A052s, or stock-size 235/265 Michelin PS4Ss. These appear to be best options based on how my club assigns points to tires.
A052 are a -5 point tire because 200 treadwear (this year's "cheater" tire IMO)
PS4S area -10 point tire because >280 treadwear.

With 225/255 A052 I have to be at least 3206 lb. (requires full tank plus ~20 lb. ballast).
With 235/265 PS4S I could run as light as 3015 lb. but my tank-empty weight with no ballast is ~3100 lb., so with some fuel left over call it a 100 lb. advantage vs. A052.

RE71R are not an option because they are a -2.5-point tire so I'd have to run another 100+ lb. of ballast and that ain't happenin...

Might consider other 200tw tires, but afaik they are all a lot slower than A052 and given a 100 lb. weight penalty vs. wider PS4S might actually be slower.

PS4S would obviously be a major compromise BUT I only need them to be "good" for an easy outlap and then 3-lap time trial.
But then again the stock 8"/9" wheels are IMO woefully narrow for 235/265 tires...

Anyway, thought I'd post up to see what the P-car folk think...

Dr.Bill

Have you thought about the Yoko AD08R? I loved those on my Cayman R.
Others give high marks to the Hankook R-S4.

85Gold

What tire pressures are you running cold and hot.

Peter

khoahtran

A052 is a qualifying tire, it’s not going to last longer than 4 days. I usually get 3 days out of them but the tire is so addicting, I’ve gone thru two sets and just purchased two more. They just release a newer version with 7/32 so it may get another day. Nothing really beats it in the 200tw range, they are faster than NT01 and R888R. Would you be allowed to run an AR-1? They are faster then nt01 but slower then a052 by a hair yet lasts as long as an nt01.

85Gold

If the OP is TT and only running 3 hot laps then the tire should last a fair amount of time. I suspect part of his issue is starting tire pressure.

Peyer

ZDan

I think PS4S might be faster at 100 lb. less weight. AD08R and RS4 should do a lot better over more than 3 laps tho...

I start out ~30F/28R cold and bleed down to 36 hot all around.

Nankang AR-1? Wasn't on my radar, at 100tw I'd have to add more than 100 lb. more ballast, so not gonna work...

I think I'll go ahead with A052 again as I only have two more events, Watkins Glen (CW) and New Hampshire South Oval (CCW), should get through them OK, but then will have to throw the Conti DWS06s that were on the car when I bought it back on as I'm sure there'll be nothing left of the Yoks...

Thanks, all!

85Gold

You might try a couple of # higher to start. I also run TT and since we only get the out lap to build heat and tire pressure the outside can take a beating on the 1st hot lap. Might be worth a try. Let me know how they do. I am running 71R but the Yoko is on the radar.

Peter

ZDan

To elaborate on usage profile, the club I compete with does 2-day events: day 1 = 4 practice sessions, day 2 = 2 practice sessions followed by time-trials, then open track (time allowing).
So my usage per event is approximately seven 15-minute sessions and one time trial consisting of out-lap at 85%, 3 hot laps, in-lap at 70%.

They get up to pressure pretty quickly, and afaik 36 psi should be on the conservative high side anyway, I think? TBH I dunno what "optimal" hot pressure is supposed to be for these tires...

The Yoks may be a little quicker, but the RE71Rs are way more durable. On the BRZ I've put 10 track days (2 wet) on 245/40-17 RE71Rs plus a couple/few thousand street miles. Those tires are mostly slick now, but intact! Currently dailying on them :O I hope it doesn't rain!
With the Cayman I've run 4 track days (1 wet), plus couple/few thousand street miles, and the tread is separating on both fronts!

FWIW I just ordered up Yoks because only 2 events left this year. Still 225/40-18 fronts but going with 245/40-18 rears instead of 255s so I can remove 15 lb. of ballast from the frunk.

booch

Dan, I had terrible wear rates on the A052s last season; I bought them for the Glen, didn't run them on day 1 due to the rain, and they were 'corded' by the end of day 1 at New Hampshire. I can't recall if we did So, maybe 5 sessions and a TT before they started falling apart. I say corded because I could the cords, but it's due to the tire being ripped apart. I thought it was mostly due to lack of camber, since the damage was done to the outer tread block on 3 of the 4 tires.

I liked how they drove, but didn't have back to back comparisons with anything other than the OEM Yokos that the STI came with. Seriously been debating picking up a set for TT use, but after finding so much time on the RE-71rs last event, I might not. I'm sure the classing point advantage will go away next season, so at that point, they aren't as appealing.

One of my students had those Nankangs on his Civic Type R, and they felt really good. I drove on them for a session at Thompson; aside from feeling a little numb in terms of feedback, they were great. I know you don't have the same options as those of us who trailer, but I thought I'd try a set for practice, and save the better tires for TTs.

ZDan

Clam, ya got me by a 4 tenths at Palmer ya bastid! Yeah, I thought "note enough camber" when I saw the outside tread of my outside front tire was separating. But then I found that the INside tread of my INside front was also separating! Tires weren't rotated, and all events were on clockwise circuits. So more camber *might* have forestalled the left front outer tread separating, but would have brought on right front INside tread separating sooner.
Conclusion: These Yoks are short-lived and come apart at the end of their useful lives. I had to take backroads back from Palmer (which was pretty cool actually).
Whereas the RE71Rs erode away to slicks but at least don't start coming apart!

Yeah, for sure they'll go to -2.5 points with RE71R and NT01. The A052s might be a tick or two faster, but it's close. I'd sooner go with the B'stones or Nittos based on durability and to ensure being able to drive home!

Yeah, not an option for me...