It would appear that Audi was onto something years ago when it started to construct cars made primarily of aluminium. While the world and its dog was busy trying to weave more and more carbon fibre into their cars Audi stuck with the lightweight metal and only now are the rest of the manufacturers catching up. The latest to jump onto the aluminium wagon is Mercedes-Benz, with its 2012 SL-Class roadster.

With the exception of some strengthening steel in the A-pillar, and some magnesium around the rear end the body shell, the new car is made entirely from aluminium, meaning a weight reduction of 140 kilograms compared to its predecessor. As Dr Thomas Rudlaff, the man responsible for the new body shell, explains: "The effect is rather as if a heavyweight-class passenger had got out of the car and taken his heavy flight luggage, too."

This crash diet means the new car should adhere to the 'Sporty and Lightweight' philosophy from which its name is derived. More importantly the weight reduction means that the new SL should be faster and handle better than the current model. which will be interesting once the AMG tuned SL 63 and 65 models are released.

No word yet on prices or specifications but the new Mercedes-Benz SL will be officially unveiled at the Detroit Auto Show in January so expect more details then.