The msd wires an coils i couldnt tell if they made a difference or not becuase i got a tune at the same time but i did notice a nice difference. When i start it up an my shifts. But the headers an downpipe install... BIG BIG difference car has a nice idle an louder when gas is applied. An when i step on it it moves much much better than before at slow rolls an high rolls. I would say im jus about neck an neck with stock gtp power now judging from when i drove my friends gtx my power is about equal. Motor mounts an fenderwell intake in this weekend so im sure ill give a gtp a run for its money then lol.