I recently installed a new dynomax muffler with magnaflow 3' tips on my '91 camaro 3.1 because the muffler and tail pipes were rotting out... Now I am considering a cat-back system but Im not sure if its necessary to change the muffler and tips aswell. Is it possible to now just change the other pipes and cat to the same specs as an aftermarket system? What is the main difference between the stock system and the aftermarket ones? Is it just he diameter of the pipes?

 

you just need an I-pipe, since everthiing else has been replced. also get rid of the stock convertor if you still have it

 

ya thats what I was thinking. So I'm assuming the difference would be in the diameter of the pipe right? Whats the stock size? 1.5'? And aftermarhet is 2.5'???

 

i think stock is 2.25. but the dynomax is 2.5 mandrel bent pipe.