It is a short tire 24.8" and a very stiff side wall. This is the RE71r that I ran last year on my 911. This lowered my top speed in 2nd. from 72 to 66 in the 911 with my 6 speed. I needed the gear ratio since I lose so much power up here a mile high. I'm looking at Rival S 315/30/18 that is 25.5" but now Hankook just came out with the RS4 with a set for the front 275/40/18 at 26.4" and 295/40/18 at 27.1". This looks like a good choice for size if the tire is any good. About 3 years ago the RS3 was the tire to have so we will see how the early test go. Someone will test these against the RE71r or Rival S like Grassroots motor sports mag.

So you can see from my picture that it is super short but it was what I had sitting in the garage to see if it would fit. That tire has a section width 11.4" and tread of 10.3". On the other hand the RS4 section width is 12.2" and a tread of 11". Once I put the rearend back together I will mock it up with the 295/30/19 Pilot Super Sports that I have on the back of my 911 and that has a section of 11.9" and tread of 11.5" and a 26" diameter. It will be a good mock up to see how it fits. I'm hoping that it does.