For the v6 with the ihe and the cam, with proper tunning i would assume u could take at least .5 - 1.0 sec off ur 1/4 mile time.. I would get the S-AFC to control the air to fuel curve that ur gonna experiece because when u put in the ih ur gonna be running very lean to ur gonna need to re map ur fuel setting to help with that..for right now there is no need to get a FPR unless u were using forced induction.. but getting the cam setting is vital, so make sure the do it right...