DOT street vs. R-compound vs. Ontario slalom rules

John Mahler

SPECIAL TO THE STAR

Q: The 2008 CASC Solo 1 rules have changed. It gives us three different types of tire choices for competition: an ultra-performance "stickie" with only circumferential grooves (Hoosier?) and move up a class; an R-compound performance tire (with a defined tread-pattern) and stay in your current class; or run any DOT performance tire and go down one class rating.

I'm thinking of moving down a class, not up. And so I need a very high-performance DOT street tire suitable for the track. What would be the best DOT high-performance tire? If it needs to be shaved to 50 per cent tread depth, that's okay too. I need a P215/45R17.

A: I think I understand the rules you are working under, but they seem silly to me. All R-compound tires are DOT approved street tires. Some R-compounds do not even have the letter R on them anywhere (Pirelli Corsa). So what does the technical committee have – a couple of old geezers sitting in front of a fire with their pipes and cuppas making rules?

So wrap your head around this: my first choice by miles in a P215/45R17 DOT approved high-performance street tire is the Bridgestone RE-01R. Horror of horrors it has the dreaded R letter in its name. But it is not an R-rated tire. Bridgestone is just fooling with people's heads because they do not make an R-compound tire.

It's listed in the consumer catalogue as an ultra high-performance tire with a treadwear rating of 180, traction A, temperature A. So run that by the rules committee. That should be enough to move down a class, and believe me, this tire has lots of stick.

If they bring up the fact that Bridgestone school runs this tire on their F2000s, be sure to point out that the school has always and will always run on street rubber, according to Brett Goodman. Speeds get too high in formula cars on R-compound tires.

If this tire doesn't fit their bill, next choices in order are: Pirelli P-Zero (the new one, has no second name), Michelin Pilot Sport PS2 and the Goodyear Eagle F1 GS-D3.

Good luck with the letter R.

Email tire questions to John Mahler

at thetireguy_1 @hotmail.com.

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