Published on August 19th, 2013 | by Daniel Sherman Fernandez0
Think Blue. The Efficiency Of DSG
What’s the most important aspect of the driving experience? The truth is that there isn’t one particular part of a car to look at when pursuing a good driving experience, but rather a whole combination of components working together. The feedback through the steering, the way the suspension reacts to the road, how the engine delivers its power: all of these contribute to a good driving experience.
But one part that manufacturers often overlook is the gearbox. That small (or in some cases, large) connection between the engine and the wheels, the channel through which the power flows, plays a large part in the driving experience. Whether a gearbox is smooth or jerky, fast or slow, or even how it sounds, can all have an adverse effect.
Purists will tell you to choose a manual gearbox. I’m inclined to say that they’re right: having 3 pedals and an H-pattern gearshift definitely makes for a lot of fun. Sadly most people aren’t prepared to drive a manual car, given the potential inconvenience in a traffic jam. Through most of automotive history, the alternatives have been quite bleak: sluggish automatic gearboxes that sap power, or even worse: a continuously variable transmission.
No, there’s no great feeling associated with these gearboxes, and more often than not they can be a slight turnoff. Granted, gearbox manufacturer ZF has made some pretty big advances with their 8-speed automatic gearboxes that shift quickly and smoothly, but those gearboxes only come with the more expensive cars.
But a few years ago, Volkswagen decided to try something a little different. The Direct Shift Gearbox, or DSG as they called it, combined the very best aspects of an automatic transmission and a manual transmission, achieving both through a completely innovative design. Two gear lines, each with alternating gears, and two clutches to match: instead of engaging each gear in sequence, the gearbox rotated between gear lines, achieving seamless gearshifts. The result was a gearbox that could shift and respond quicker than a manual transmission, with the smoothness and convenience of an automatic transmission. It was the best of both worlds, and soon this gearbox found its way to nearly every model in Volkswagen’s range.
There were other benefits to this as well. One of the problems with a conventional automatic transmission is that it uses a torque converter, which saps power and efficiency. A lockup clutch can mitigate this by over-riding the torque converter, but very few transmissions had a smooth lockup clutch that could engage in every gear. The lack of a torque converter in Volkswagen’s DSG gives it an edge on efficiency compared to a traditional automatic gearbox.
Throw in the fact that the latest iteration of the dry-clutch DSG systems has 7-gears and you have a very robust, practical, usable gearbox. Leaving the gearbox in “D” offers a very smooth driving experience, and with such well-spaced ratios the systems rarely have to hunt to find the right gear. The systems are designed for maximum efficiency and enable the gearbox to achieve 5.9 litres per 100 kilometres fuel efficiency, depending on the engine it is paired with. Pop it into manual shift mode and you have full control of your gearing, especially if the steering wheel mounted paddle shifters are present. DSG is the perfect combination of convenience and control, almost to the point where manual transmissions may become redundant.