Quote:
Originally Posted by ///M4ster Yoda
There are plenty of DCTs out there that can handle higher amounts of HP/TQ. Porsche, Lamborghini and Ferrari are all using them. BMW wants to cut costs so they can make Electric Toyotas with Roundel's on the hood. Wait they are already doing that  :
Using a ZF8 in an ///M car is a travesty. It might work for the Land Yacht M5 crowd but won't work out to well for BMW in the M2/3/4 models. |
The reason mid-engined and rear-engine cars mostly use DCTs is because of packaging. That's why the traditionally torque converter auto Corvette is going with a DCT for the mid-engined C8. Can you imagine trying to fit a planetary gearbox in the back of a longitudinally mounted mid-engine car? That transmission simply does not exist.
That's also why transverse front-engine performance cars usually go with a DCT if not a manual (like hot hatches). A high performance torque converter auto is impossible to fit in a transverse configuration. That's why the RS4/RS6 have a ZF 8HP but the RS3 still has a DCT. If the RS3 were longitudinal, it'd have a ZF 8HP, I guarantee it. Notice that Honda only makes a manual Si and Type R? Or that VW only offers the option of a DCT or manual in their MQB platform cars?
An auto is an auto. They perform almost exactly the same. In fact, if you told someone that the new ZF 8HP M3 had a new DCT with smoother clutches, there'd be no reason not to believe that. Shifts are blindingly fast when tuned for a high performance car (don't use your wife's X5 shift speeds to make a decision about how all ZF 8HPs shift) and the engine is locked to the input shaft of the transmission except when you're starting from a stop. So there's no slushbox feel associated with cheaper and older automatics.
DCTs were lauded as being the supreme compromise between auto and manual, but then ZF made an automatic with constant lockup which removed the inefficiency of the torque converter, smoother 1st gear starts because of that torque converter, and actually lighter than comparable DCTs. Not to mention that plenty of cars with torque converter autos are absolute track monsters and modern ZF 8HP and Aisin 8 speeds shift faster than previous gen DCTs. The slight speed advantage that DCTs have is not even possible to translate into faster acceleration anymore. It's just a number people write on forums to tout some imaginary advantage that their (non-automatic in their heads) automatic transmission has. It's just an automatic transmission. The car does all the work for you, all you do is press the go pedal and you're off.