I'm curious whether Z4 3.0si wheels will fit on an M (style 135 or 203). I have a set of 135s that I currently use for my Z4 in the winter, and would prefer to keep them if I can when/if I get an M Coupe.
The front/rear sizes are:
8x18 ET 47
8.5x18 ET 50
All wheels are fitted with 225/40R-18 winter tires (same size as Z4 fronts).
Based on the calculator at
http://www.rimsntires.com/rt_specs.jsp, the diameter would be almost 1" shorter and the wheel would be 0.2" closer to the suspension/brakes both front and back. Is this perceptible/safe?