I have a 2002 Cavalier LS Sport with the 2.2L Ecotec. I bought the Hahn Racecraft Stage 2 turbo kit for it and I can't wait to get it installed. My question is, does anyone know the diameter of the downpipe that comes with the Hahn kit and also what is the best diameter of exhaust that I should use to accompany this turbo kit. The largest catback system I have found was 2.5" from Vibrant. I was planning on having a custom exhaust built for my car and that was going to be 3". However, i heard that 3" exhaust is a waste and will not give me any improvement from the 2.5". Does anyone have any opinions on which diameter I should use and also, should I have a custom exhaust done or just go with the Vibrant? Thanks
nah it will help
www.customtubesinc.com ask for willy
LE61T PTE6262 Powered 
The downpipe is 2.25". I have the same kit and I am going with 2.5" mandrel. If you plan serious upgrades for huge boost in the future go 3". For leaving the stage 2 as is 2.5" would most likely suit your needs.
"If you aren't shifting, then you certainly aren't driving!"
