Don't know what a stock Gen IV puts down but with my heads reworked by Bischoff Racing Engines, a 708 cam, slow bleed lifters, 1.7 Harland Sharp RR, and a SCT tune by Pickups Plus Cars my 2001 has 550 RWHP which would be about 640 at the crank. I'm running the factory exhaust manifolds, HF...