I have seen the shorty header that you can get with a 2.25in downpipe with highflow cat, I havent seen a full length for the Ep3 but have found them for the rsx. My question is would the hp gains be that big of a diff to buy the full length instead of the shorty?? Also somone mentioned a upgraded midpipe with stock muffler sounding good?? please explain. was this just a custom made straight pipe to the stock axel back. Looking for hp but not too much noise, this is for my dads o4 si. He says the g spec on my eg is way too loud.

 

well I don't have a EP3 but I do have a DC5. The longer headers as I understand will give you better midrange and high end. if you are looking for more power race headers make the most power but they don't have cats. therefore they aren't very restrictive. IMO I would get a race header because I have seen dynos from shorty header and they don't make that much. I'm about to put on a DC5 R header with the cat. i'll let you people know how that runs.

 

Well my plan is to run A full length header (no cat) and a 2.25 midpipe to the factory rear section. I have a feeling this will work perfct for what i am looking for. Anyone know the rear section pipe diameter.