11-29-2012, 10:51 PM
Worlds Foremost Authority
Location: Upper East Side Manhattan - Lime Rock CT
Join Date: Jul 2007
Mein Auto: 2015 M4 Convertible
I have been saying for a while that the best of the conventional "Slushbox" transmissions were very close in performance to DCTs and in many cases were smoother. The torque converters in the best of the ATs are locked up once the car is in motion and the truth of the matter is that torque converters are very good devices for smooth starts.
Originally Posted by -=Hot|Ice=-
The ZF8 is one amazing transmission. I still can't get over how smooth it shifts. You'd think you were driving a twin clutch.
I think a lot of the appeal of the DCT is that people can convince themselves that "it isn't an automatic transmission" in spite of the fact that in terms of shift speeds, performance, and user interface, a state of the art AT is virtually indistinguisable from a DCT.
A while back Ms. Audio and I test drove a 335is with a DCT and a Jaguar XKR-S with a ZF 6 speed within a few days of each other. After we drove the Jag I told her that it had an AT while the BMW had a DCT and I explained the difference between the two types of transmissions. She told me she did not see much of a differnce and if she had to say which one she preferred it would have been the Jaguar. FWIW Ms. Audio is very adept at driving an MT. Although we have had a few AT Jaguars (XJ8 Sport, XJ8 VandenPlas and XKR) in Florida until the 335i (and now the 750) our NYC cars were always MTs.
Edit: When I test drove the XKR-S the Jaguar representative who rode with me was Davy Jones (24 Hour LeMans winner, drove in the Indy 500, Nascar, etc,). He has been working with Jaguar for a number of years and is an instructor at test drive events. He is a casual acuaintance of mine and as we were driving the XKR-S he told me that he had recently driven a Lamborghini Adventador and he did not like the Lamborghini transmission at all and much preferred the Jaguar tranny (which is a ZF 6 speed similar to the Steptronic in the E9x 335i. Jaguar has programmed it differently for the XKR-S. He felt that the Lamborghini transmission (a single clutch 7 speed auto) shifted much too roughly and tended to upset the balance of the car.
Drivers Club at Lime Rock
The Glen Club (Watkins Glen International)
International Motor Racing Research Center
Cayman Club Nor'Easters
Madison Ave. Sports Car Driving and Chowder Society (Only a Vice President)
Sports Car Club of America
Polish Racing Drivers of America (PRDA)
American Mural Project
Simeone Foundation Automotive Museum
Mount Washington Observatory
Society of Automotive Historians
Last edited by captainaudio; 11-29-2012 at 11:02 PM.