i first put k and n 's air intake kit onmy 02 v6 camarowith stock exhaust and was rather impressed with the sound and jump in power response. so a few weeks later i put an american thunder cat back exhaust on the car and now it seems to be less powerful and the gas mileage sucks. even if i drive normal and smooth with no racing the engine im getting round 40 miles less to the tank then before. it doesnt even seem to bring the front of the car up and fly if i neutral drop. HELP. can anyone tell me if i reduced needed back pressure or is a simple question of fuel to air mixture? would a tuner or chip help, and if so any brands recomended.
much appreciated,
meister

 

front of the car up and fly if i neutral drop. HELP.

maybe too many of thoughs.....