Im must admit that im a tunning freak and love to modify and tune my cars. I have already got supersprint exhaust, K&n air-filters, Dinan comp. upgarde, Dinan stage III suspension, f+r stut bars, short shifter, and no cats for my M5. Hartge is coming out with camshafts and headers that will give you a cool 50hp. Im still waiting for the price for it. And Dinan is coming out it with the dual cold air intake in mid to late Nov. Their supercharger will be out in 9-12 months. Keep it up guys!!!