Wheel-Tire Theory

This valuable Wiki page was re-created from an excellent thread started by Hapa88 in March 2010

I’ve seen countless threads here asking about Offsets and Rubbing, as well as trying to get that “Flush Look”.
Well I’ve created a few PowerPoint slides to try to explain how everything works. And I’ll post some pictures showing my experiences with NSX Offsets and fitment.
Here are the slides I created, and I’m open to comments on how to better them, as they are to serve as tools for NSX owners.





Below are some examples from some of my setups:
For the Fronts:
18×8 +35 with Falken FK-451 in 215/35/18 (these tires run narrrower, so note the tire stretch and sidewall angle – very minor rubbing on high speed cornering)

18×8 +38 with Kumho SPT 215/35/18 (note how they are still slightly stretched – this was my best setup, practically no rubbing at all)

18×7.5 +30 (the outer position is equivalent to a 18×8 +36) with Kumho SPT 215/35/18. Note here that because of the 7.5″, that the same tire as above is more squared off. This equals TONS of rubbing. . .so much in fact, that I had to shave off 4mm off the back of the wheel to get a +34 offset (and I still rub!).

For the Rears
There is no rubbing on any of the follow setups:
19×10 +30 with Falken FK-451 in 275/30/19 (again, the tires run narrow, and note the “stretch”)

19×10 +35 with Kumho SPT in 275/30/19 (note it’s more square)

19×9.5 +23 with Kumho SPT in 275/30/19 (note it’s even MORE square because of the smaller wheel width)