[Adam]

Originally Posted by bmwm750

I have the new FabSpeed exhaust, and unfortunately yes, it does drone in the 2-3k range. I am still on stock headers, but am looking for ideas there. The FabSpeed headers are gorgeous and I am sure will not cause any CEL related issues, but damn are they pricey.

Heres my latest idea for a perfect exhaust for these cars: High flow catted headers (a la FabSpeed) to guarantee improved flow and scavenging, yet also no CEL related issues. Secondary cat deletes. Now, heres where I would like to think I'm onto something: Stock 03 muffler, but with RPM activated dump valves (almost like turbo wastegates) BEFORE the muffler section, that begin to open at say, 3500 RPM, and are fully open by say, 4500 RPM. With this design you have a perfectly quiet car for normal driving and cruising, with no resonance issues, yet when you get on the power, as the RPMs rise and you get into the meat of the power curve, you get a very free flowing exhaust, that will sound glorious as well.

Anyone else think this could hold some promise? I have a very qualified shop here that could do the work on designing a system like this, and we could have a prototype I'd be happy to test.

Patrick

Bogg tried some valves like that on his stock muffler and the results...well lets just say some people liked it and some didn't. It didn't sound very "exotic." I'll try to find the videos he made. I do like the idea of using the stock muffler though with headers and bypass pipes. I think that would make a good combo.

http://www.youtube.com/watch?v=08-uX9z_Rg4

http://www.youtube.com/watch?v=vpXhUN6-vsk&mode=related&search=