Yes they will fit without boreing the cylinder walls. However, once you take out the stock pistons you might find that the cylinder walls are scored, and need to be honed or bored over to take out the imperfections.
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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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