Ok, i just bought a 2002 cavy with 2.2L ecotech w/ 5 spd and was thinking about putting some new headers and when i got to thinking about putting it on, i may as well put in a new exhaust system. so, any recommendations on type of either, i'm thinking catback exhaust. is there anything else i need to do to make it run properly? also, i know there needs to be back pressure in an exhaust system, now i just don't know why, what's the purpose? thanks.

Either Magnaflow, DynoMax or Borla for the exhaust. As well, I'd think about getting a resonator too! I hate it when cars go screaming down streets in 2nd gear... but that's just me!