Some final calculations prior to ordering wheels. I plan on using the Toyo R888R's with a 265/35 front and 315/30 rear. Using the specifications provided by Toyo I was able to calculate the overall tire width on 10.5" and 12" wide wheels.
Based on my calculations the front maximum tire width will be 11.1" and the rear will be 13.0". I made the tires in CAD and plugged them into my model. I also plugged in 2.8° front camber and 1.8° rear camber. This results in a 2mm clearance from the tire to the inner fender panel in the rear and a 9mm clearance in the front. More room in the front will allow me to run a 275 width if I feel I need to in the future. I am going with the 265 so I can get a small amount of stretch on the 10.1" tread width to preload the tire for better handling and feedback.
It will be interesting to see how accurate my calculations are when the wheels/tires come in.
Front: 265/35 Toyo R888R | R Disk 10.5" width 4mm offset | 2.8° Camber
Rear: 315/30 Toyo R888R | A Disk 12" width -2mm offset | 1.8° Camber
Another factor I considered was the overall tire diameter. The stock setup is 24.77" front and 24.75" rear, so approximately flat. The new setup will increase the height by 0.5-0.7" to 25.30" front and 25.44" rear.
In theory, I believe this will be the widest setup that offers the best handling possible for an e82.
This may seem overkill, but I haven't found any E82's using a clinched widebody for a track oriented car. They all seem to be
stanced. Some guys are running 13" wide wheels, but with massive camber angles and tire stretch.