goujon

i have a 97 turbo 2000 uk facelift, ive installed a blitz sus induction kit and blitz bov and it has an sti intercooler and manual boost controller, but not done exhaust yet, when i got it MOT'd there was a small hole near back box causing it to be just shy on the emissions test so got it welded, its a 2.5" with 1 cat and now i think its starting to blow a little so want to know if i should just swap it like for like with another 2.5" 1 cat or go for a 3" with 1 cat. obviously id like to go for a complete decat exhaust but cant be arsed with putting a cat back on for mot, is there any difference in power gain between 2.5" & 3" with 1 cat apart from sound...

bigsinky

the difference is not noticeable unless you are running big power