Since its launch last year, rumours regarding a convertible version of the Mercedes-Benz SLS AMG began to circulate on the internet. These rumours were quickly confirmed by spy photographers, who captured AMG engineers testing roadster test mules in different parts of the world.
Recently we published a story about the roadster undergoing final testing at its home ground in Germany. But now Mercedes-Benz has finally released details of what is to be its top- of-the-range convertible. The SLS AMG’s compact cloth fabric top was chosen for three reasons: It is lightweight compared to a folding metal roof, its trim folded dimensions don't impinge upon boot space and its styling is remeniscent of the original 300SL Roadster. Capable of folding away in just 11 seconds, the roof can be operated at speeds of up to 50 km/h.
As is the case with the SLS AMG Coupé, the Roadster is made from an aluminium spaceframe (weighing 243 kg, only 2 kg more than the gullwing model) with that well-known 6,2-litre V8 engine pushed as far towards the rear of the engine bay as possible. Channelling 420 kW and 650 N.m to the rear wheels via its seven-speed DCT dual-clutch gearbox, Mercedes-Benz claims an acceleration figure from 0-100 km/h in 3,8 seconds for the SLS AMG Roadster. The Roadster's top speed is electronically limited 317 km/h – the same as that of the coupé.
Additional weight?
As is the challenge with most roadsters, once the roof has been removed, the engineers need to strengthen the chassis to compensate for the resultant negative impact on the vehicles torsional rigidity. Apart from the spaceframe, the body is also made from aluminium. To increase rigidity the side skirts have greater wall thickness as well as more chambers. Higher up in the car, AMG has turned its focus to the dashboard cross-member which is supported against the windscreen frame while the centre tunnel receives additional struts. Towards the rear a curved strut has been places between the soft top and the tank that reinforces the rear axle. Even with all the soft-top’s roof mechanisms and these extra support structures, the Roadster tip the scales at 1 660 kg, only 40 kg heavier than that of the Coupé.
Among the optional extras on the launch model will be the AMG ride control (a system that allows the driver to select three different damping settings: Comfort, Sport and Sport plus). As with the Coupé, the Roadster will be available with a three-stage ESP-system and a differential lock to help put all that power from the wheels onto the tarmac. Ceramic brakes will be another option. Apart from offering better braking performance, the ceramic brakes also offer a 40 percent weight reduction compared to that of the standard items.
Frankfurt unveiling
Mercedes-Benz confirmed that the international unveiling of the SLS Roadster will happen during September’s Frankfurt Motor Show.
The SLS AMG Roadster will be available in right-hand drive in the UK from November 2011, so expect it around the same time in South Africa or shortly thereafter.
