Originally Posted by TrackRat
Minimal throttle position causes high engine pumping losses. BMW conducted extensive testing years ago and determined that WOT in a higher gear delivered better mpg than low throttle opening in a lower gear for acceleration. At a constant speed like on the hwy. running the engine rpm close to the torque peak in an N/A engine delivers the best mpg, (the lowest BSFC). In a forced induction engine you need to find the balance point for boost, throttle opening and engine rpm, which can vary considerably based on the vehicle and engine.
Thanks for that - brilliant info! Truly the S65 is built to perform! I can see it now...
"Sorry Officer I was trying to save fuel by driving really fast!"