2 1/4" he's gonna rub with anything that's a 205 most likely, at least on u-turns. 205/40/17 and 205/45/16 are nearly identical overall tire diameters. I would go with 16's, just because I think 17's look too big.
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2015 Ford Mustang GT Fastback - Ingot Silver - 6M - Performance Package - Gibson Catback, JLT CAI, FR 47lb injectors, BAMA E85 tune, Eibach Sportline, BMR wheel hop kit, UPR oil separator, Steeda shifter bushing/bracket
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