The other day I biult a new rear section exhaust system and welded a 3" flange to the muffler and tailpipe so I could change it out for another custom made on when I wanted to. When I went to weld the other flange to the intermediate pipe I realized that it was 2.75" pipe! The car had the dual dual on it and I thought that it was 3" but I fugured out that SLP only put the damn muffler and tips on the car and not the whole cat back. Needless to say I was a little upset. I fabricated an adapter for my new muffler but my question is how mutch is the stock pipe holding my car back? I am going to order some MAC headers in the next few weeks and I am guessing that this pipe will not help flow at all. If worse comes to worse I will just but a new exhaust system w 3" inermediate pipe. Any help is appreciated in advance, thanks!

Brian

 

Anyone?

 

No difference what so ever. Derrick Red? ran a few tests in the quarter mile and there was no difference in ET between a Dynomax muffler on the stock i-pipe and running open cutout just after the cat before the i-pipe. As for your SS, SS is 2.75" mandrel, Z28 is 2.75" crush bent. The tests were on the crush bent, so safe to say you're getting upset for nothing.

 

Thanks, teach me to get upset. Thanks for the response..

Brian

 

Yep, biggest problem with the stock exhaust is that it's compression bent, not mandrel. I believe SLP used 2.75" mandrel bent pipe because it flows plenty for most engines and yet will pass noise tests.