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      03-26-2008, 09:29 PM   #85
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Drives: E92 M3
Join Date: Sep 2006
Location: San Diego, CA USA

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Originally Posted by ersin View Post
I don't think you're wrong. DCT should be less jerky than SMG due to the fact that there is no/less let up of throttle between shifts.

SMG shifted fast but there was still a moment of time where the clutch was disengaged during new gear selection and acceleration practically stopped, then when the new gear was selected and the clutch re-engaged acceleration resumed. Hence the jerk.

DCT has the next gear pre-selected (not all but most of time I would guess) and therefore no waiting for the gear to change. Just change clutches.

The jerk we are talking about here comes not from the re-engagement of acceleration but the extra energy stored up as engine rotational kinetic energy (angular momentum). My thought is that you will feel less of a jerk but more like a surge. I guess that make us SMG drivers jerks compared to DCT drivers.
Mostly correct here but when SMG shifts, just like a MT the car does not "practically stop accelerating", in fact it noticeably and measurably decelerates!