Hello all- I have just purchased a 2001 X5 4.4i and I abdolutely love it. :redspot I am a new BMW owner and am lookin to start doing some modifications to the engine. Where have most of you started? I enjoy the power (hate the gas mileage, but I didn't buy a Honda and Toyota plug-in) and the ride, have the early nave with the tape player on the side and i am about to add the cd player(I think the original owner pulled it and put it in their new car). So all you X5 heads- where have you started- tell me the good and the bad so I can make the right decisions. What don't u like about your X5? Thanks for your help. Visiting family on the West Coast and will post pics when I get back to the East Coast.