Dinan Tune for 4.4itt
I have to agree with everyone else, these new 4.4i turbo motors are strong to begin with, and incredible with software tuning. I was the first in Michigan to get the Dinan tune for the new 2011 X5 50i, and I can tell you 500hp, and 573lbft of torque make for one fast 5000lb suv. This thing pulls like a train from 75 to 125, it even feels stronger in the 30-50mph range than my Dinan M6 convertible. Seat of the pants feel gives me a o-60mph time somewhere around 4.5 to 4.7. A stock X5M was clocked to 60mph by topgear at 3.9 seconds. My X5 stock is supposed to do 0-60mph in 5.1 per BMW but it felt faster to begin with. I would assume a 550i with the Dinan tune to do it somewhere closer to 4 seconds. To give you an idea, there is a stretch near my house where from the streetlight to the first tight bend (pontiac trail in commerce) where if I accelerate from the light I would be around 50mph by the first bend. With the software tune, I am now somewhere closer to 65mph. It is definitely much much stronger and on the verge of what I would call stupid fast for a SUV.
Noushy