When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I don't think there's a "right" size for all NB cars because the fitment depends on the wheel diameter/width/offset, and the setup of on the specific car. The common R7 sizes I have used on NB are:
front 225/40-18 (24.7" tire height)
rear 315/30-18 (25.6") or 295/30-18 (25.3")
front 245/35-18 (24.4")*
rear 315/30-18 (25.6") or 295/30-18 (25.3")
front 255/35-18 (24.8")*
rear 315/30-18 (25.6") or 295/30-18 (25.3")
front 235/35-19 (25.6" tire height)
rear 315/30-19 (26.1")
*denotes wider front tires require rotating the front top plates and associated setup work.
Also, depending on the track, some tracks is better to have front tires that are at least 0.5" shorter than the rear tires to keep stock ABS happy.
Hi Tom---I run the 245/35 & 315/30 18" R7 set on my 997.1 GT3 dedicated track car and wonder if you decided any of the other setups felt like they planted better than than the 245/315 combo. I'm running an ExE-Tc suspension at the soft end and is working well, but any 2nd opinions appreciated before I start fiddling with ***** or something.
This may sound strange, when I was younger I races superbikes weekly, expensive and dangerous even though I couldn't careless at the time!
Now with a family I traded all that in for a 6gt3 setup for the track a number of years ago. I have zero desire for a dedicated race car, I know what the red mist brings!
when my son is old enough will likely invest in a cup, purely for safety!
^ so u were a dare devil.
6 cup is good safety.
i have factory race cars but i dont race anymore. sometimes, well maybe all the time, being safe is a good thing.