I got tons and tons of stainless steel 3in diameter pipe for free and I'm really itchin to use it haha. Right now I'm running no cat with a cherry bomb(sounds like complete ***). What I'd like to do is run a Thrush welded muffler with a 2.5 or 2.25 inlet and 3in outlet and then run the 3in pipe out the back. I'm hoping that the stock diameter pipe and muffler will give enough back pressure and that the 3in pipe will give it a deep sound.

Otherwise I'll just delete the cherry bomb and put a Thrush welded in its place.

Any thoughts? Bad idea? Good idea? Better idea?

I'm on a quest to make a 3.9 V6 sound good(or atleast decent)

 

It sounds like a good plan. You don't have to worry about back pressure. Even with 3in all the way there will be enough. It doesn't need much at all.

 

My .02: without the resonance chamber/cat, your exhaust is probably "raspy" in the upper rpm's. Tell me if I am wrong. Not sure of the gauge your using, but thicker pipe will yield a more mellow tone.

 

It is somewhat raspy as it is right now. The 3in pipe is a little thicker then stock exhaust so I'm hoping I'll get the tone and sound I'm looking for. I'll let you guys know how it all goes next week when I install it

 

Yeah, the 3 inch is stock on the v8 - sounds amazing. It attracts all the ladies...but they stop running when they see my truck.

 

If you want to decrease the rasp-master sound, then you either put a larger muffler on or add a resonance chamber (cheaper). An older method was to wrap the muffler with a material that is no longer available. The 3" pipe will give a little more meat to the exhaust, and the longer- the lower.

Here is a decent basic article on exhaust theory. It is noted that the secondaries are the most important aspect of exhaust design.
http://www.superchevy.com/technical/...xh/index1.html