Quote:
Originally Posted by Serious
The difference I perceived is noticeable at high RPM where the G80 feels like it ramps down engine torque prior to and after the shift to save the gearbox. The DCT has no torque ramp at the shift so it feels faster and more dramatic.
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Yup this hits the nail on the head. Put putting around casually there really isn't a difference in total shift speed between the two, other than DCT still sounds and feels like a clutch clamping. The magic happens at high rpm / heavy load where the DCT is effectively powershifting with 0 torque drop off whereas the ZF has to ramp down torque due to its planetary design & clutch packs. That's the difference and that's the reason why a ZF (or other current auto) can never emulate MDCT shifts & "immediacy" no matter what the tuning. It just is what it is, there's really nothing to argue about here. Mechanically, DCT can't do the auto thing as well as ZF, and ZF can't do the gear-slamming thing as well as DCT. But they both do a decent
impression of each other.
Really though, we're talking about relatively fine margins here and it's not gonna matter to most people who buy this thing. Could G8X have been better with a DCT? Maybe, but ZF fits what G8X (and the rest of the current BMW offering) is trying to achieve so I'm inclined to believe that DCT wouldn't jive as well with the total package.