Quote:
Originally Posted by kyrix1st
Quote:
Originally Posted by lemetier
That aspect isn't going away. Like M-DCT and PDK-S, brake release does not engage forward creep automatically.
PDK is not 7ms - 8ms for a gear change. I don't know of any Transmission capable of such and that's faster than any No-Interrupt Electrical Transfer Switch can achieve. Porsche publish "less than 100ms" for gear changes in the Lightning Shift mode on PDK-S, and "less than 200ms" on PDK in Sport with Chrono.
The torque converter does not "lock up gear each time". It goes to 100% lock from a standstill before 1000rpm in Sport+. It does not unlock again while in motion, even during a shift. Only the shifting elements after the TC manipulate shifts and they are sequential, overlap, clutch-to-clutch through the full range.
What vehicles with this same transmission have you driven?
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6ms in a roughly 1cm travel distance of clutch engagement is very possible. Do the math and you get the horizontal velocity of 1.67 meters per second, which is 1/455th of a bullet travel speed (760m/s.) And electric transfer switch what? Speed of light is 3.72E5 times the speed of bullet. 
By this transmission, do you mean ZF8HP? I've never owned one with it, but I've driven 120d, M135i, Audi RS7 (pre-facelift). I didn't say I dislike it, I just think it doesn't quite fit the M character. ZF could be fast, but you can't argue you don't feel as connected as that of SMG or DCT. Downshifts never feel as firm.
Other ones I've driven (haven't owned them all except E60 for brief period) E60 M5, F82 M4, F10 M5, Cayenne (tiptronic) and Panamera S. PDK feels faster than the current Getrag DCT in the M.
Thinking of getting a low mileage E63 coupe/F87 (two very different cars I know) in the coming months but torque converter is unlikely to be on my priority list for the enthusiastic driving. Overheats way too quickly and goes into limp mode; sucks for prolonged high rpm (>7000) driving. Ever noticed how ZF doesn't like you shifting at the redline? Their limit is 7500rpm before shit starts breaking down |
I think it's a bit unfair to compare a M DCT with a std car transmission. The std VAG DSG is miles apart in feel and shift speed to a PDK...
Not sure where you have the overheating claims from, but the ZF 8-speed works pretty well in long distance racing on the Nurburgring in the M235i Racing... The only modifications to the transmission is electronics, no mechanical changes over the std version in the M235i. I would suspect that any overheating problems that you imply this transmission has should be evident during the 4 and 6 hour long races in the VLN cup at the Nurburgring. Not to mention the 24 hour race at the same track...
The shifts seem pretty quick in this onboard at Spa Francorchamps BTW...
And this video teaser from BMW indicates pretty quick shifts and aggressive downshifts