I have a 03 ecotec 2.2l. I have CAI and Headers 4-2-1 headers 2 1/2 high flow cat and piping back to dual exhaust with no resonator. Is the duals costing me hp and mpg. I know i have more air flow leaving then coming in is that effecting back pressure. I want to supercharged it but not for another year so should i get rid of the dual set up and just keep the single exhaust. and my car is raspy because i have no resonator should i put 1 before the dual split if i decide to keep it or buy 2 resonator 1 for each muffler please help thanks

I dont think the duals is really doing much unless its true dual exhaust. if its y piped and splits to two its just more for looks wit the dual tip i dont think you are necessarily loosing power but it is unecessary weight..not alot but it is. as for putting the supercharger on i dont know much but forced induction but i believe itd be better to upgrade teh piping size i know ppl with turbos usually run piping around 3 '' for the exhaust. i would keep it single exit tip. thats just me personally thats what i got..don know if this helped but good luck.

personally i think duals on a J are a waste of money. just go with a good full exhaust

which of these plays a bigger part in the tone of the exhaust based on resonator. I have none on the car the shop that did the work took it off. Im buying a resonator probably 2 /12 and either 14 or 16 long. is the length or diameter play a bigger part of the tone