i changed the headers, up and down pipes and stealth back and the car seems to be making more noise than it should. additionally, i dont think the turbo kicks in because the car has lost a lot of power. also there is some smoke and smell coming from the turbo and no CEL.:confused:

PS: GT-Spec Headers and uppipe, TurboX Stealthback, OEM muffler.

The smell and smoke is prolly because it is new and is burning off the residue oil or paint. It should go away is a short time, should. Headers do make the low end punch not as hard, but the power band is more linear and you can rev past 6500rpm without the power dropping off. The oem muffler is a bit restrictive considering you are running a free flow up front. Also, you may have to reset the ecu. It has to learn all over again since you modded the engine. I have the Maxim headers and my car did the same thing.

Sounds like a leak in the uppipe to me.