Tire Size
 

So i am looking at getting new tires for track use only - interested in the toyo R888r and currently have 18X9 rear wheels. It looks like 265's are hard to come by, can i get away with 275's in the rear.

I know some folks that are running 235/40/18 front and 275/35/18 in the back in the R888R - the diameters are only slightly larger than the OEM sizes - this weekend they are running their first track day in that tire, if you wait until Saturday evening I can report back and let you know how they were.

thanks, will keep a look out. hope they work out okay

I will be buying tires in the spring and 275's in the rear would be nice.

Not trying to insult anyone but taller tires means less acceleration

wheel tire combination impacts performance in different ways:
increased wheel size with decreased tire height but increased width increases traction but decreases mileage but not performance up until 19s so stay within 17 - 18s wheel size with appropriate height/width and you'll see increased aesthetics and performance gains.

The 275/35/18 didn't work this weekend, they rubbed, maybe due to wheel offset issues. I don't have any more details than that, but wanted to give a quick follow up.

Edit: it was offset issues with a 10" rear wheel, issue resolved going to a different wheel.

I have 265/35/18 on turbo twist wheels

I've seen people with 997 turbo wheels in 19" and others with 996 turbo wheels in 18". I have a second set with 993 turbo hollow spoke with r-compound that i use on my turbo. Have been thinking if they work on the Boxster. The turbo uses 285/30 - 18 tires.

If it works with the above cars maybe it's better to buy wheels that work and matchning tires.

What he said. There seems to be two ways the tire manufacturer make their brand 225/40/18 and 265/35/18, or 235/40/18 and 275/35/18. either go on 8" front and 9" rear. I do use a 17MM shim on the front and a 7MM shim.

Seems to me that that the wheel-size.com calculator will answer a lot of questions.