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[lilg1993]

Ok, let me start this by saying this is not a generic "what size spacer will fit on my e9x 335?" thread. I am using my own knowledge and experiences with calculations and other measurements, but I feel like I am either doing something totally wrong or missing something completely.

My summer setup is OEM 359M's on Michelin PSS, and I have minimal rubbing that does not bother me...only over large dips/bumps. Exact wheel specs as follows...

Front: 9jx19 ET+31 235/35ZR19 (91Y) XL
Rear: 10jx19 ET+25 265/30ZR19 (93Y) XL

For winter, I just had Pirelli Winter Sottozero 3's mounted on my OEM 313's. Exact specs are as follows...

Front: 8jx19 ET+37 235/35R19 91V
Rear: 9jx19 ET+39 235/35R19 91V

Now, according to this calculator, the 313's should have an extra 19mm of clearance up front, and 27mm in the rear. The way I understand this is that if I were to [hypothetically, since they don't exist] throw 19mm spacers up front, I should expect the same rubbing parameters. Is this somehow flawed thinking? My own measuring of my gap just now yielded approximately .25" (6-7mm) from fender lip to the "widest part of my tire" [as the instructions from ECS/turner tell you to do it]. Am I measuring from the wrong part of the tire?

Similarly, with the rear, I measured approximately 11/16" (17-18mm) using the same methods. What am I doing wrong/what am I missing here? Any help would be greatly appreciated.