I don't think there's a difference between LS and GSR clutches in terms of clamping force. If there is a difference, it's so slight that I can't tell when driving a GSR. I know that the ITR has a slighty higher clamping force.
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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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