Thread: S65 vs. S62
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      01-25-2013, 05:33 PM   #97
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Drives: 2008 E90 M3
Join Date: Jan 2012
Location: Mill Creek, WA

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Originally Posted by bruce.augenstein@comcast. View Post
Your example of punching it from cruise in third gear at 6000 rpm is an example of jerk from the takeup of driveline lash when going from light-loading cruise to full power.

Look, I'm not saying that the jerk factor is immaterial. What I am saying is that it's of little consequence in terms of a building torque curve.
I would tend to agree that more of the jerk comes from drivetrain lash in this case. The nice thing about the M3 is there is almost no jerk from a changing torque curve over the RPM band, and the torque management parameters used to tune the ITB openings at various RPMs and throttle position (drive-by-wire makes this possible) allows a predictable amount of torque at any RPM for a given throttle position. It's really quite amazing.