Mike in Chi

There have been some very favorable threads on these tires lately, as well as the current Pano article, and the Pano autocross tire test article from last year.

They sound like great tires.

But some of the posts talk about the tires taking a little longer to heat up and grip.

Question: If you're using them for autocross, have you had a problem with this?

Last year's Pano gave them high marks in the test, but their runs were consecutive, so obviously the heat would build up.

Our region's autocrosses are run such that you sit 10-15 minutes between each run.

I'm wondering if the tires will get good and grippy, or be to cool to really stick?

(By the way it's a '97 993 narrowbody on 17" cup wheels which hopefully will have ROW M030 by next spring. I'm thinking 225/255.)

Thanks in advance,

Mike in Chi

Ed Newman

I have them on my 996 and they are NOT a good auto x tire. I won't say they are bad, I still managed to win my class at the PCA Zone 1 Auto X with them, but they are slow to heat up and hence do not stick too well. They are by far the best rated track tire, but you are better off with Kuhmo's for Auto X.

JJayB

I've tried them on my 993tt for a PCA driver ed. time trial at Willow Springs big track, which is notorious tire killer. After all the hype I thought these might be the ticket. Wrong. These tires had no grip comparded to Hoosiers also I didn't like the sudden breakaway on high speed turns. I got them up to 180 deg. and was off 2 seconds on my lap times compared to Hoosiers. On the positive side they wear like iron and don't seem to need as much camber as Hoosiers. I'll give them another shot with softer roll bar settings to see if that helps, but I doubt it.

James Achard

Jim, What tire pressures were you running?? They should be at 35 psi hot. Many folks I've seen make the mistake of running them like Hoosiers with 43psi hot. These tires don't like that. I hope this helps.

Cheers, James

JimB

This summer I had one set of wheels with Hoosiers (245/285x18) and another with Cups (265/285x18). On several occasions I ran them back to back and while I would agree with Jim that the Hoosiers at their best were a bit faster it certainly wasn't 2 seconds. I would say more like .5 or so. I'm pretty sure that if you were able to measure your times over the life of the tires the Cups would come out ahead. I found them to be more consistant from new through cords.

As for autox, I only used the Cups once and that was in the rain where they did fine but as a rule I would say they take far too long to warm up to make them effective for short runs. Even with 265s on the front of my 996 it pushes like crazy for the first four or five laps at the start of the day. Especially whey the Cups are new.

Alan Herod

What tires besides Hoosier Autocross tires heat up to operating temperature by the last turn of an autocross, let alone the first. It seems that only special compound (rain or autocross) or a good street tire would achieve optimum temperature. The Michelin, a shaved Kuhmo, or Toyo would provide benefits because of more contact patch and a stiff side-wall, not because it reached temperature. If it weren't so they would not make more then one or two laps on a road course before they way over-heated.

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Mike in Chi

thanks for the replies, guys, I appreciate them.

Greg Fishman sent me a link to Michelin who says for autocross you need to at a higher cold pressure than for the track (track is 25-28psi f/r cold) because of "the decreased pressure gain in autocrossing".

Jim and James-

That Michelin piece said they should be 32-36 psi hot

Ed-

Which Kumho tire do you recco for autocrossing? Thanks

Mike in Chi

NineMeister

I had the Sport Cups on my 993RS CS last year for out PCGB Speed (Hillclimb & Sprint) Championship. I was a second off pace all year due to the slow warm up time of these boots. I tried all sorts of pressures to no avail, I could not get them to hook up at all on the first lap. I notice that the treadwear rating is 80.

This year I found a stock of Pirelli P Zero C tyres and bought myself two sets. The treadwear rating of these is 60. Immediately I was on pace again, and knocked 4 seconds from my previous time of 100 seconds on a double lap sprint on a small circuit.

I had problems with the Cups in the wet as well, nearly losing it in standing water on the road and track on many occasions. I am not a fan of this tyre at all, and would go as far to say that I think the qualities of the tyre should be questioned w.r.t. its suitability for road use. However, get them hot, get the pressure right and they stick like glue.

Another Euro tyre that I can recommend is the Dunlop Formula R D01J, on a par or slightly better than the Zero C in the dry, warm up quickly, are forgiving on the edge and are cheaper to boot. Hope this helps.

JJayB

James Achard
Re: Tire temps. I ran 33/36 hot on the michelin cups. In fairness, the Hoosiers were wider tires 245ft and 305 rear vs. 225 ft and 285 rear for the michelins. Checked my log and tires were off 1.8 seconds. Thats pretty close to 2 sec.
I had 8 run sessions and worked my tire pressues up based upon the tire temps and mfg data.
If I'm within one second of the Hoosiers and I get and extra weekend out of the tires then the Michelins would be worth it to me.