From Car Craft Magazine. Finally, we swapped on the stepped X-pipe setup and were impressed to see power levels equal to the open headers: 335 hp at 6,300 hp and 302 lb-ft at 5,200. Thats a gain of 12 rear-wheel horsepower, although it turns out we werent really giving anything up or gaining anything extra from the open headers. So the cars happy, and our ears are even happier!
