I had no cats/no side muffs on my car and made 440 rwhp. No loss in power here!. I just recently bought a snakeoyl rear assembly (no rear ****). OMG. I don't think I can drive on the street anymore. Sound is very cool, and I'd like to take it to the track like that. Too loud for everyday use but probably picked up another 10hp based on sound levels
I've got some high flow cats to tune it down a little now. I hope the swap will keep me at 440rwhp while staying emissions legal.
I do not believe you are losing any power with the straight pipes. The bellanger headers are a tri-y design with 3" collectors, designed for mid range power. The stock exhaust should be 2 1/2". This is the size exhaust you usually run with a 3" collector and 400-500 hp. Most people run 3" ex. because henesby (the original viper tuner) used it with his 5-1 headers and big hp vipers. And bigger is better, right?
If you had a head/cam motor with 1 3/4" 5-1 header (like b&b) and had 550-600hp, yeah, you might see a small gain with the 3" exhaust but the muffs would keep any gain minimal (10hp?). Thinking of running the borla ex without muffs? Think stock car loud! Remember, You need a little back pressure for optimum performance.
My '95 has bellangers and 3" high flows and dynomax race bullet muffs. I really believe that a 2 1/2" system would make just as much power with its 400rwhp. The lack of back pressure now really pops in the exh during decel. Its pretty cool. I may swap out in future just to prove my point to everyone, but I've also got a cam that's just waiting for those headgaskets to blow!
