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      11-14-2012, 11:19 AM   #1
ERinEC
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Accelaration Delay When Shifting Down 2 Gears With DCT

I just bought my 2011 E92 M3 a little over a month ago and when downshifting from 5th to 3rd there is a noticeable delay in the car responding and accelerating. Drivelogic was set to 4 when this occurred.

Anyone else expericence this?
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      11-14-2012, 11:34 AM   #2
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Its because the 3rd and 5th gear are on the same shaft within the DCT so the box requires longer to make that shift as it cannot preselect 3rd gear when you are in 5th.
Bypass this problem by shifting down one gear at a time or down shifting 3 gears.
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      11-14-2012, 12:28 PM   #3
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ahh that makes so much sense. I had also wondered why a double downshift took so long. I don't know why I didn't think of that.
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      11-14-2012, 07:37 PM   #4
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BTW, even with this slight delay, the shift is still faster than a 6MT

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      11-14-2012, 08:48 PM   #5
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Quote:
Originally Posted by SenorFunkyPants View Post
Its because the 3rd and 5th gear are on the same shaft within the DCT so the box requires longer to make that shift as it cannot preselect 3rd gear when you are in 5th.
Bypass this problem by shifting down one gear at a time or down shifting 3 gears.
+1

Odd gears are on one shaft and even gears + reverse are on the other.

Here's a good general writeup on dual-clutch transmissions;

http://en.wikipedia.org/wiki/Dual-cl...ansmission#BMW
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      11-14-2012, 08:57 PM   #6
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Quote:
Originally Posted by CanAutM3 View Post
BTW, even with this slight delay, the shift is still faster than a 6MT

LOL!!!! Could not help to laugh!!

But please, no, not again.......
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