i need help bad
whats actually goin on with the car; whenever i try to turn the key over it backfires, a couple trys later it'll start up. before my headers were put on (with just a fra and a cut-out) i kept up with a 01 z with intake.... but after my headers and true duals (no cats no mufflers) im losing by a car length or two.... could this be because of no backpressure cuz of the no cats or mufflers? or maybe the camshaft position sensor which is more than likely a serious problem?
if you have any suggestions id appreciate them
thanks
-eric

