The car is an 01 M6 mods are TR224 cam unported 243 heads with cometic .040 gaskets making the CR to 11-1. jethot LT headers and Y going to a cutout before the axle. K&N FiPK Intake and a ported TB on the stock LS6 intake the car has also been tuned.

 

390 to 420 if you'r lucky and your clutch isn't slipping ..

 

when does it go on the dyno? I would say 400-410 to the wheels.

 

Should a stock LS6 clutch with 20k miles be slipping at this power level?

 

My stock clutch would slip under less power -- luck of the draw for those that don't experience these problems. Went to an LS7 clutch and it's held 600+ rwhp for a good while now!

As for the power estimate, I would imagine you're in the 390 - 410 range at the wheels.

 

Yup my buddys car had basically the same setup as you with ported 243 heads and he put down 426.

 

no you will be just fine