What is tge best tune for it for as dinan .oe tuning. Ecuprogram. Activeautowerke. Which will be the bedt choice???? The best airintake for it ?? And exhaust system gor it ??? Anyone can help thanks

 

I think Active Autowerke makes some great stuff. I don't know much about modding the 550i though.

If you wanted a car to mod and get lots of power I'm afraid you purchased the wrong car. The 535i is what you want for modding.