Yes a gutted cat will sound like bees.
I never said a high flow cat wasn't worth it, but you'd see bigger gains with a more modified engine. With only I/H/E, you won't get too much out of one. But with cams, higher compression, FI, etc, you will get lots out of it.
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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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