Milling the head is a waste. Bigger injectors are also a waste right now. The GSR cams will make a little more power, but go back to stock injectors...you don't even have a built motor. If you were running 12:1 compression and big cams to like 10k rpm, I'd say get some bigger injectors. Be careful about spinning that stock LS block to 8k...the rod bolts probably won't last long.
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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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