Mazda launched the transmission last October as
-Drive. It will first be available this year in the Mazda3 and Mazda6.BMW uses aeight-speed torque-convertor automatic but has successfully enhanced the box. speaking at the BMW 6-Series launch in Cape TownBMW has about a dozen patents on the changes and is earning "a nice income" from licenses with companies including arch rival Audi.
"Dual clutch technology in passenger cars is about seven or eight years old," he says. "It is suited to engines that have a high engine speed and that's why it is currently in our M3. A torque convertor has - at the moment - limits with its operation above 7000rpm engine speeds. For all other applications, we have three versions of our eight-speed automatic that are better than the dual clutch."
The BMW M3 dual clutch has 160 millisecond changes, so they're virtually the same,""The automatic is 12kg lighter than the M3 gearbox and - comparing the two gearboxes on the same petrol engine - gets an 8 per cent reduction in fuel consumption. On a diesel engine, the automatic gets a 9 per cent fuel saving."within seven years" there will be another big leap in transmission innovation - but he isn't giving anything away"it's not yet ready".We know thathas a nine-speed automatic and that Chrysler will be one of the first manufacturers to use that transmission,""But we won't. It is possible to go to 12 gears, but we are happy with eight. The problem is that, and we have tested this thoroughly, a nine or 10-speed version of the eight-speed automatic offers no fuel economy improvement. It adds weight, is expensive and is less efficient because it has to operate on three open clutches (which draws engine power). Our eight speed operates on two open clutches, so it's economical and lightweight."A manual gearbox is still cheaper to make than an automatic,""The 6-Series, for example, has a manual option and it's popular (and exclusively available)
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