For the E90 E91 E92 E93 3 series and E89 Z4 a 235/35/19 with 265/30/19 would be best. These are 19" x 8.5" et35 front and 19" x 9.5" et43 rear. For the F30 F31 F32 F32 3 and 4 series the factory 225/40/19 and 255/35/19 can be used but a better option is 235/40/19 and 265/35/19 to cover the rims better and provide a better ride with more tyre profile.
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