i have a mk2 1.2 v8 and i want to tune the engine i searched for the air filters and i'll buy a K&N 57i and i want to tune my exhaust i searched that the stainless steal is good for it but i didn't find a one can any one tell me what is the best type to buy or can ask a mechanic to build a new one for me ? and i want a sport spark plugs which one i should buy ?? and is there any idea else to tune my engine more then that ?