10 degrees is way too much. The only way cams should be moved is with adjustable gears, and even then setting the cams 20 degrees apart, I don't think that would run too well. Cams should be tuned on a dyno, because every car is different.
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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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