klarksen

I know form experience that my Audi lost alot of power when I made an exhaust with just one silencer instead of four (incl cat). How is it with the v8? I now have two silencers, one flowmaster and one original. But not impressive sound actually. If I took away the original, would that cost me any power?

chaadster

I don't have the numbers to prove it, but it seemed like I hAd less low end responsiveness when I was running straight pipe in place of cats. Can't speak to max hp, though.

JHowell37

If you remove a stock muffler and replace it with something like a flow master, I doubt you'll lose any power. I don't think you'll produce as much extra as they claim however. There has been a lot of research in exhausts to determine what works and what doesn't. The Louie Ott article from Excellence a few months ago does a great job of explaining the x-pipe. Your best bet is to use the search function.

marlinspike

When you lower backpressure to much you lose some bottom end power. The trick is to find that sweet spot. The exhaust shop that built my exhaust, which builds exhaust for Nextel Cup cars (i.e. NASCAR) and NHRA cars put a Y-pipe rather than an X-pipe and two Bassani mufflers for my car (5.7 liters, high comp pistons, flowed heads and exhaust ports), partly because of my lumpy cams, so that the engine would make the most power under the curve, rather than just the most power.