What will gain more hp, stock exhaust with test pipe (2.5") or aftermarket exhaust with cat (3")

Trying to figure out what the most cost effective way to go for the short term is.

Thanks EVO HEADS

 

im going to do some testing tonite on a stock 03 evo 8. im going to pull a graph and see what gains are made by adding a 3" TP. without a tune and no other mods. i also have some logs of an evo 8 with an open QTP cut out. i'll post up late if ur interested.

 

Do you mean TBE on the 3"? If so, I would say option #2, but I don't have any data to back that up. I have read before that going with a test pipe over a high flow cat didn't net much - on the order of 1 - 5 whp.

 

the best route is a turboback system. Good HP gain. A tip for savin some cash, miragepower2008 on ebay. $245 shipped you just have to win the auction bid, but its not an issue really. I have it and it is a great system, not just for the price either. good quality and materials plus all hardware and gaskets. Im gunna post pics pretty soon.

 

well for some reason i cant get my pics from my cameras memory card onto this computer... WTF? Ill put em up as soon as i find out whats up.

 

Thread Resurrection,
whats the average HP gain with a 3" tbe w/ test pipe with no tune? And then with tune?