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DesertDude DesertDude is offline
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Posts: 6
Join Date: Dec 2013
Car: 2013 335is Convt.
Default 09-04-2015, 03:38 PM

Based on my experience with the DCT and tuning, I would tend to agree with BuraQ and Musc in this situation. The "droop" in timing you see after the shift appears to be the engagement period of the clutches in the DCT.

The DCT uses timing adjustments to manage torque during clutch engagement. On a good "hard" shift, there is almost none that is perceptible in any log that I've seen. In a slower "sloppy" shift where you can tell the DCT is not engaging quickly, you see a timing adjustment or droop as shown in your log. (I have seen worse).

The RPM slope fluctuation after the shift seems to also match up with a delayed clutch engagement, straightening out once the clutches are fully engaged and timing is no longer being adjusted by the transmission. This further seems to point to a delayed in clutch engagement.

This behavior is why I previously recommended that DCT cars not disable Torque Reduction by Ignition as it won't allow the DCT to properly adjust torque for smooth engagement.

Just my $.02 based on my experience.
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