Originally Posted by Mrbig
2011 m3 the 17x10 will
Fit no issues all around ? Lowered on kw3s ???
The 17x10" ET25 with a 275/40/17 will have the same issues as the 18x10" ET25 with a 275/35/18 does with KW's progressive V-shaped springs. With the KW Variants/ ST Coilovers, you would hit either the spring perch or the bottom of the spring itself with the V shaped springs, not the strut itself. In order to fix this issue with the 18x10" ET25 wheel clearance, you would want to use at least a 5mm spacer, or to switch to a linear spring. Because of the linear spring's shape, it is recommended to be used with camber plates. You may be able to source upper top hat that would work with the OEM upper mount.
The KW spring perch accepts a 60mm spring, thus you should look for a 6" 60mm spring from Swift, Hyperco, Eibach, or H&R. This will allow you to remove your V shaped spring and raise the lower spring perch higher.
With OEM suspension or coilovers with short linear race springs that keeps the spring perch above the wheel and tire, the 17x10" ET25 does fit without any issues.