when ever flow is changed up its a good idea to reset fuel trims. once fuel trims are settled in they can adjust some, but to what extent i dont know. its better to just go ahead and reset them and let them settle in to the new mods. the 04+ guys fuel trims take longer to settle in, ive heard a few days. the older 03- guys does not take as long, ive heard up to an hour of driving.
when i put my headers on i dident feel a the full diffrence for about a week either.
performance shift is on the underside of the gear shifter. some cars did not come equiped with it. i think its 98-02 models. not sure.
