Your OEM rods are fine with the ARP rod bolts. OEM valves will be fine too. Flat faced valves will raise compression very slightly, but the difference is negligible. You don't need stronger valves, but lighter valves will move a little faster.
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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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