Per the list of my mods below would the addition of a plenum really make a noticible diffference to a car that already IMO halls ***? i'm no 700hp but im plenty fast for my taste - its just for 1k this seems to be an efficient mod - then again i bet the 3o hp gain is on a bone stock motor . . . would i need to recalibrate the softwatre if i wanted to add it? I looks like a plenum would make a difference but am curious with an approx sub 4 second car if it's even worth the $$ . . . thoughts? thanks guys