Originally Posted by Dodge2Dub
What is the ideal 17" size for the E9x M3?
It depends what you are using them for. 17x10" fits square on the car. That could be used with 275/40/17 r-compounds easily.
17x10.5's are an easy rear fit, and could even be used as a dedicated drag setup.
The new 17x8.5" ET20 wheel can even clear a Brembo or Stoptech 355mm kit on the E9X M3, so they could even be light weight winter wheels for someone with a BBK.
There's a lot of different uses for them
Let me know how you would use them, and I could provide a better wheel/tire recommendation for that application.