Hello everyone. This is my first post, just bought a 91 Camaro RS with a 305 TBI, but it does not have any exhaust from the cat back. It has stock exhaust manifold, a y-pipe that is full of holes and stock cat. I was thinking of putting on headers, new y-pipe and a flowmaster cat-back system with 3" pipes. I dont know if 3" is too big for my engine, or what kind of headers I should get. I am not really looking for hp increase. Just no exhaust to speak of right now and I figured now would be a good time to put somthing decent on it. Any info would be great.

 

Go with 1 5/8 Headers and then a 3" in & out Cat with a mandrel bend 3" pipe to the muffer and dual 2 1/2 outlets. This should work on 305.

 

I would just stay with 2 1/2" all the way, but we all have our own opinions. with that little 305 (which is probably a little tired also), you do want to keep some decentback pressure. you don't want to be one of those guys that stomp the pedal and all the car does, is make a buch of noise and goes nowhere do you?

also with a nice 2 1/2" system, you won't have to worry about as much interior drone. just my two cents