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      08-24-2008, 04:31 PM   #47
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swamp2's Avatar

Drives: E92 M3
Join Date: Sep 2006
Location: San Diego, CA USA

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Originally Posted by footie View Post
Based on the evidence that swamp has uncovered the whole lag after flicking the paddle is purely interest and has no real bearing on the performance of the car. Acceleration seems to be unbroken with DCT as all the manufactures have claimed and with surge there is a slight increase during that 200ms transition from one gear to the next, the only benefit with discovering to amount of lag at different levels is to learn why it's there at all.
Absolutely agree. But this data was not needed to realize that. We all knew simply from driving that all acceleration continued truly as if nothing had happened in the period between the paddle actuation and the beginning of clutching! What is novel is the the surge seems to occur across the entire shift, not after it.

Originally Posted by footie View Post
We all know that SMGIII might quote a shift in 80ms but I doubt anyone believes that to be the case, I have read here that some reckon it's closer to 180ms which even using the none surge modes mean the DCT improves on this by up to 5~6 times. One can only imagine what difference it will bring to the likes of the M5/6, RS6 and other truly bonkers cars.

I will be interested to see how quick the shift can actually be after additional testing, is it truly possible that DSG and DCT actual shift in the often quotes 8ms. That's mind blowing.
We have seen accelerometer data from an M5 (or M6) showing the ~150 ms number. The suspicion is about half and half clutching vs. moving the synchros. BMW chose to report half the picture. Again my strong hunch is we may see 20 ms or so on D modes from 6->7th but 8 ms, VERY doubtful. This is going to be very difficult to test as well. It will require a WOT shift from 6->7 due to signal to noise, that is fast!