« Another sluggish for the Japanese market in 2008 | Home Page | Mazda Demio Chiara special edition »
Volkswagen's first seven-speed DSG for Golf and Golf Plus
By Yoann Besnard on 21 December 2007 | 
(0) Comments | Permalink
In a previous post I talked about the two awards given to Volkswagen for its TSI family engine and I mentioned that the 1.4-litre petrol engine was associated with a DSG gearbox. At that tine, I was wrong as it was only available with a manual gearbox, but I'm now right as Volkswagen has announced that its seven-speed twin clutch gearbox will be featured as on option with the 1.4-litre TSI petrol unit and the 1.9-litre TDI diesel engine on the Golf and Golf Plus models.
The DSG is an electronically controlled, twin-shaft dual-clutch manual gearbox, without a conventional clutch pedal, with full automatic, or semi-manual control. In other words, it is two separate manual gearboxes, contained within one housing, and working as one unit. Compared to an automatic gearbox, the DGS offers several advantages. It has an extremely fast shift time of 8 milliseconds when shifting to the gear the transmission is expecting, has practically no power loss, due to the use of clutches instead of a torque converter and offers a better fuel economy than the planetary geared automatic transmission and manual transmission. But it also has its problems. When shifting to a gear that the transmission did not anticipate, shift time is lengthy with a roughly time of 400ms and the DSG is heavy: 75kg vs. 47.5 for a comparable manual gearbox.
The latest iterations available on the Golf and Gold Plus adds to new features as well. Firstly, it is the first DSG for front-traverse installation. Secondly, it is the first with clutches that are not immersed in oil, but which run “dry“. This allows the latest Volkswagen DSG to achieve an even greater level of efficiency. The maximum torque that can be transmitted is up to 250 newton-meters.
The 1.9-litre TDI engine associated with the seven-speed DSG has a consumption of 0.7 litres per 100 km lower than the same engine hooked up to the six-speed DSG transmission.
