I believe back in the day, that-company-who-shall-not-be-named tested the stock clutch to 450+ ft-lbs. But I'm sure that's just for casual driving. Trips to the drag strip or just launching in general will eat up the stock clutch in no time with that much torque.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |