Another slick option for the GT3:

255/35/20 and 315/30/20 or 325/30/20

https://www.toyotires.com/product/proxes-rr

 

I’ve always liked Toyos. Too bad the 325 is not a 25 series (would help maintain the OEM gearing).

 

The overall diameter of the 315 RR is 27.5 and the 325 is 27.7. The OEM Sport Cup 2 is 27.2.

You think this would effect much?

 

Only a ~2% difference. Not ideal, but not too bad. I’d prefer to have shorter than stock gearing though if it was to change, but this is certainly close enough to try.

Also be aware that the load rating on the two Toyos is a bit less than stock (101 and 102 for the two sizes vs. 103 for the stock Cup2). I’m told this is pretty important for the rear of a 911.

 

Good to know

 

Ran these on my E90 M3 a few years ago and loved, loved them. Much faster than Nitto NT01s, but they do wear twice as fast too. Just be aware of an important technical bulletin that was released for these tires--while they appear symmetric and non-directional, their construction actually requires that they be run in a certain direction so they don't delaminate. I'm sure you can find the bulletin on Toyo's site. You're able to tell correct mounting/location based on DOT date code location on each tire.

 

Good info.

I found the bulletin you are referring to: https://www.toyotires.com/media/1488...mmendation.pdf

 

I ran these regularly on a built Terminator after exhausting the Nittos. Granted it was a straight line car, but the tire stood up to ~650tq. The sidewall did better than the nitro as well when the rear got squirrelly.