thats wot they say, bluefin say i get an extra 10bhp, k & n say i get an extra 10 bhp, so my car should be 168bhp, i bet it wouldnt be if i roll and roaded it. i did here once your st engine is warn in you can extra 10bhp a goo engine. i think mine maybe a good one cause i only had my bluefin had a little play with another st, i had four ppl in the car and he was by himself i i stuck with him. you be best buying a bluefin mark, for £300 adds 10 bhp so they say, ford cant detect it and you can switch it on and off when you like.