From last year, the front runners in the street and clubsport class were all running either michelin sport cup 1's, pirelli p zero trofeo R's, or Yokohama A048's. I was the only one on R888's that was competitive.

Granted this is not a sure indicator of what is faster since the market here is prohibitive to buying non TUV approved tires which is likely why that specific selection of tires was seen. The Hoosiers fall under the not TUV approved realm and the fact that I can't visually pass them off as having a street tread would probably make the inspectors bump me up a class.

Its an odd setup since teams cross from country to country for the time attack series and the rules are not the same between them e.g. Poland, Germany and the UK time attack series all have very different rules. The inspectors/organizers know this and leave rulesets very vague.

 

The website is back up. Under tires for the class it says :

Es dürfen ausschließlich Reifen mit EKennung verwendet werden. Die Verwendung von Slicks ist ausdrücklich verboten. Die Lauffläche der Reifen muss vom Kotflügel abgedeckt sein. Für ausreichend Freigängigkeit muss gesorgt sein.

or :

Tires must have an E number (think of this as the euro version of DOT). The use of slicks are absolutely prohibited. The tread of the tire must fit fully under the fenders/guards. Tires must have adequate clearance.

So its pretty open so long as they have an E number. The hoosiers in all forms won't work.

This limits my selection to the following:
Federal 595 RS-R (garbage, these threw tread blocks on me)
Toyo R888, R888R or R1R
Yokohama A048 or AD08R
Michelin pilot sport cup 1 or 2
Pirelli Trofeo race
Dunlop direzza 03G
Hankook RS-3

The rivals *Might* get past inspection but would open me up to a protest later.

 

Are the Advan A050 or Hankook TD not allowed or not available in Europe? I would have thought the hankooks would be, seeing as how they have a pretty big footprint in Europe and sponsor a number of racing series over there (DTM in particular).

 

The TD's might be.. There was a forum post saying they are E marked but the hankook Germany website does not sholw it or mention it.

 

Some more discussion here:
https://my350z.com/forum/wheels-and-...inch-rims.html

Post #9 is what I was looking for... an optimized ratio.

 

The ratio stated is not matching conventional wisdom at this point. A 10.5 inch wide rim at 1.2 would put it at 12.6 inches of tire. On a R888 that would be a 315 width tire. I'm thinking its going to be closer to a 1 to 1 ratio for serious track enthusiasts.

That being said, it looks like I'll be moving to Hankooks TD C5's this year. I'm just waiting to hear back what the measured width is on them before I decide to go 285 or 295.