2.5 complete exhaust VS a 3.0 complete exhaust

hardcore5657 said

I just got dougs headers. Now i am going to do a x pipe or h pipe dont no which one yet and either 2.5 or 3 inch exhaust. I have a 360 with 10 -1 compression, rhs magnum heads, comp cam with .545 lift, edelbrock magnum air gap intake, holley 770 carb. I don't no how much HP i am making. Does 3 inch exhaust sound to big. Will I lose bottom end torque or is that just a myth?

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I talked to Doug Thorley personally about 1997 about all of this. I actually got the third set of Doug's Headers for the early A when he reintroduced them. I got them for 500 bucks delivered. Nickle plated. I had a very long conversation with him. He's a nice old dude. He said that he had done extensive dyno testing at that time and any form of crossover pipe had little to no effect and in some cases lost power. It was completely contradictory to what everybody else was claiming at the time...and still claims today. He said that it was all marketing hype. He also said something else that I completely agree with. that any form of crossover lessens the exhaust tone. That is, takes away from the exhaust note. Makes it sound "less crisp" if you will. His words, not mine. He also said that going up from the collector size showed no gains either. Hell, he's still kickin and workin everyday. You can probably call him yourself.