dont know what exhaust system or headers!
 

hey guys i just bought a 03 lancer ce gli 1.8l, manual.
its stock everything running perfectly fine. but in my opinion is really slow.
now i dont want to put turbos or anything extravagant like that in.
i just want to install a full performance exhaust system including headers and also a K&N air filter.
can someone please help me out and tell me whats a good combination and if it will actually give me any performance gain from them mods?

p.s i will be getting a good tune after i install these things in aswell :)

thank you in advance :)

actually dont worry about headers. i was just wondering about what kind of exhaust and cat comverter i can install to get alittle power and acceleration gain.
someone please give me some help/??