focus st170 exhaust manifold and a de-cat pipe to match and a cat back exhaust which wil give some more power and sound and a quick fix for more power is buy a 2.0 block and swap it for you 1.8 block after that your looking for cams ect..

you already have a body kit on the car in fact the only one better is the focus rs which is an easy fix done on the fron but not cheap and really not cheap on the rear as you have to remove the whole rear wings.