hi there iv got a focus rs its got a blue fin de cat and a mongoose exh the next mod is going to be a manifold bot wot one .Primary desighns do one but its big money over a grand so iv been on to buma speed who have one made by hks in japan are there any others i can try or has any one done this mod with wot results cheers .The car did a 14.1 at avon race way so its quick as it is we always want more