9. Like the rest of the exhaust plumbing, all the Corsa components were stainless steel, mandrel-bent, and designed to bolt right up with no cutting or fabrication. A chambered high-flow muffler provides a nice sound while eliminating highway drone. The exhaust system upgrade combined with the cold-air intake brought peak horsepower up to 286. But more important to Paxton is the fact that the truck was now primed to take full advantage of the supercharger.