Thread: 6MT question
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      12-04-2011, 12:21 AM   #18
jetblackcoupe
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Drives: 2008 e92 335i 6MT
Join Date: Apr 2011
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Quote:
Originally Posted by The HACK View Post
You drive a turbo-charged car with single throttle body and electronically controlled direct fuel injection and a hydraulic lifter. You want to be able to keep the foot buried and side-step the clutch to keep maximum acceleration? You'll need to have a carburetor equipped engine with individual throttle bodies and a solid lifter. On the N5X engines, the RPM is programmed to stay high on shifts to keep emissions down as well as keep the boost up (in the case of the N54/N55) to prevent too much lag, plus the hydraulic lifters and electronic throttle map will never allow your engine to respond that quickly to throttle changes.

My final advice to you is, if you want to achieve the FASTEST possible acceleration time? It's not going to be possible to avoid some jerkiness in between shifts when you dump the clutch. Even the last generation SMG, in the most aggressive and fastest shift mode, you will feel a hammer on the back of your @ss every time you shift because, well, there's a difference between engine speed and road speed. ONLY on DCT type transmission where there's two flywheels and two drive-shafts engaged at all times where it is possible to NOT feel that change in gear, because the next gear is already spinning at the same speed as the engine.

Or ditch the N54/N55 and go with any of the naturally aspirated M engines. The individual throttle bodies makes the engine rev up and down almost as quickly as your foot can move, and those cars are tuned to produce far more smog than your run of the mill BMW engines so they're not programmed to "hang" up high in rev to keep NOx emission down (as much).
thank you, much appreciated
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