If you are leaving your fronts with factory dimensions and 245 width, then I would leave the rears with the same ratio to the front, and go with a 275 in the rear.
If you're willing to increase the front width, then go wider in the rear.
275/305 here
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| 2015 Nismo headlights| 275/305 | Z1 spacers | Eibach Pro-kit |k&n typhoons | AAM S-Line catback + FI test pipes | Stillen splitter |
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