Hey guys i was just wondering i was told by a guy at the locval exhaust shop that my cat. converter is shot. There are metal shavings in the pipe goin to the muffler and he said its in the muffler too. He said he thinks that more then half my converter is blocked. What kind of gains would isee by throwing on the american thunder cat back. no cat. on it either. I have shorty headers running into a 2 in y -pipe(yea it sucks but its the only thing that fit with the oil pan)

 

first things first, junk that y-pipe. im not sure what oil pan youre using, but if its anything close to the norm, you ought to be able to get a decent y-pipe to work. even a muffler shop can make one better than what you have. as far as actual hp gains, im not going to give it a guess, but it would definitely be a noticeable gain and well worth the money spent.