Ps. and this same guy sometimes runs 305 Kuhmos, which happen to fit his 12 inch rim, while the 295's will not.

I have 315s mounted on 11 inch rims on a widebody GTS3 turbo 944 and they fit fine. I personally don't think I'll ever go beyond 285s for my SP3 car, since the S2 HP limit will make it difficult to drive such a large/heavy wheel combination. For those with 968s or Turbos it might be worthwhile, but I doubt the advantage is that significant. I believe the Hoosier chart shows 11-12 inches as recommended width and that the 315 dimension was measured on an 11 inch rim.

The 12" width will give the tire a better profile and shape, and should also minimize tread-area carcass heat variances better.

For one guy shows up at Daytona to influence the rules and "might" show up with 2 more cars. Not posting here, I don't know. Dave , we could turn your second last comment around and argue the oppsite way.Again I believe no one Super ran big 295 plus size tires, the F class turbos run 275/285 max. Also no ran flared fenders in super cup until Daytona. We can build "Frankstein ($$ Super cups) , but I beleive that will only last a year or two then Super cup will slowly decline in numbers. More is not ALWAYS better.

PS, the ($$ is a slip of caps loc, but I left as is to get the point across.

Maybe we should just go back to the original proposal, 10 inches all around.

Thanks everyone for your comments.

I would be behind that, as well as an overall max width of the car, including any flares....

Do we have a consensus on the 10 inch rim limit?

With a wheel/tire limit and a limit on spacers, no need to worry about flares. Plus hard to measure and to hard to fix given we have already given the green light to flare unlimited.

I suggest that we go 11" as you can bolt on 996 rear wheels, which are 11" you can find used wheels cheap. Limit spacer size to 1 or 1.5" which you can buy from eibach/H&R .You do not need spacers if using 996 11" wheels, you need to flare the rears by a 1.5".I know because last night i setup my S2 with a 996 11" wheel, tires size used 295 as thats all I had.So if you want a 305 you might need a 2" flare. To cover 295, the wheel and tire about 1.5 flare is needed and the car will still look "STOCKISH" That will limit flare size. Do not worry about the fronts as they will be same size or smaller.

We should go with 11 inch rears and 315s otherwise many GT cars can't migrate without buying a couple of sets of wheels. GT-Racing flares are 2 1/4 inch and I Believe Broadfoot's are the same size. I don't know of any 1 1/2 inch flares on the market.

Question: why do we care about migration? cars in the gt class are to far gone to be in sp3 anyway and there are 1 maybe 2 if any at all that show up sometimes in the northern pca races anyway. Limit the size to make the class what it is a spec class not GT.