By The features of the SL body design include the long wheelbase, the short overhangs, the long bonnet, the passenger compartment set further back with a steeply raked windscreen, and the powerful rear end. They give the roadster its powerful, dynamic appearance – together with the voluminously modelled wheel arches and the large light-alloy wheels that are flush with the outer skin.
The SL 43 runs on 19-inch light-alloy wheels as standard. In addition, the same range as for the eight-cylinder models is available as an option: aerodynamically optimised light-alloy wheels with diameters of 20 or 21 inches, which reduce air resistance through low turbulence. Particularly sophisticated are 20-inch wheels with plastic aero rings that save additional weight.
An electric soft top instead of the previous metal vario-roof, with the 21-kilogram reduction in weight and the resulting lower centre of gravity has a positive effect on driving dynamics and handling. The Z-fold saves space and weight and makes it possible to dispense with a conventional soft-top compartment cover. The front header bow ensures that the open soft top is flush in its final position. At the same time, the developers were faced with the task of maintaining high suitability for everyday use and the exemplary quiet-running. The three-layer design consists of a tightly stretched outer shell, a precisely finished roof liner and an acoustic mat made of high-quality 450 g/m² PES fleece inserted in between. Opening and closing take only about 15 seconds at speeds of 60 km/h.
Aerodynamics
A technical highlight for improving aerodynamics is the AIRPANEL active air control system. The horizontal louvres behind the upper air intake are electronically controlled and can be opened and closed with actuator motors. The airflow is directed according to demand, thus improving aerodynamic performance. The optional Aerodynamics Package for the Mercedes-AMG SL 43 includes larger flics on the front and rear bumpers and a larger rear diffuser. This improves both downforce and aerodynamic drag even further. The modified speed thresholds of the rear spoiler and its steeper angle of attack of 26.5 degrees (instead of 22 degrees) in the Dynamic position also contribute to this.
Tech-savvy
The interior of the Mercedes-AMG SL 43 also features an exciting combination of analogue geometry and the digital world – known as “hyperanalogue”. This is exemplified by the fully digital instrument cluster, which is integrated into a three-dimensional visor. The standard MBUX (Mercedes Benz User Experience) infotainment system offers a choice of several specific display styles and different modes. Despite symmetry, the cockpit design creates a clear focus on the driver: The high-resolution 12.3-inch LCD screen of the instrument cluster is integrated into a high-tech visor that prevents reflections caused by sunlight. To avoid disturbing light reflections caused by different sun positions when the soft top is open, the tilt of the 11.9-inch Central Display touchscreen on the centre console can also be electrically adjusted from 12 degrees to 32 degrees.
New chassis
The SL is the first production vehicle ever from Mercedes-AMG to feature a multi-link front axle with five links arranged entirely within the rim. At the rear axle, a 5-link design likewise controls the wheels.
To reduce mass, all suspension links, steering knuckles, and wheel carriers on the front and rear axles of the SL are made of forged aluminium. The multi-link concept controls each wheel with the least amount of elastic movement. The lightweight coil springs are a new development: special tempering allowed their weight to be lowered without reducing their performance. In the manufacturing process, the spring pad is glued onto the spring for the first time. This firm connection prevents wear and tear caused by dirt over the course of a vehicle’s life. The spring does not corrode over the life cycle and the maximum component load can consequently be increased at less weight. Another lightweight construction measure concerns the torsion bar stabilisers on the front and rear axles of the SL 43.
Performance
Under the bonnet is an in-line four-cylinder petrol engine with two litres displacement that provides the befitting propulsion. This is the first time in the world that an electric exhaust gas turbocharger is being used in a production vehicle, technology from Formula 1. This form of turbocharging guarantees particularly spontaneous throttle response across the entire rev range, thereby offering an even more dynamic driving experience while increasing efficiency at the same time. The turbocharger is operated via the 48-volt electrical system, which also feeds the belt-driven starter-generator (RSG). As a result, the Mercedes-AMG SL 43 has an output of 280 kW and a maximum torque of 480 Nm, plus an additional short-term boost of 10 kW/150Nm from the RSG in certain driving situations.
The four-cylinder engine, which has long been used transversely in Mercedes-AMG compact models without an electric exhaust turbocharger, is positioned longitudinally in the SL 43. The engine is also combined with the AMG SPEEDSHIFT MCT 9G transmission (MCT = Multi-Clutch Transmission) for the first time. The elaborately calibrated software ensures extremely short shift times as well as fast multiple downshifts if required. In addition, the intermediate throttle function in the “Sport” and “Sport+” driving modes delivers a particularly emotionally appealing gearshift experience. There is also the RACE START function, which ensures optimal acceleration from a standstill.
The driving performance is up to par: from a standstill, the SL 43 accelerates to 100 km/h in just 4.9 seconds and the top speed is 275 km/h. The SL 43 has comparatively low consumption and emission figures.
The newly developed AMG high-performance composite brake system guarantees excellent deceleration and precise control. When the ignition is switched off the parking position “P” is also activated. When starting off, the electric parking brake is released automatically. The Mercedes-AMG SL 43 can be equipped with active rear-axle steering as an option. Depending on the speed, the rear wheels steer either in the opposite direction (up to 100 km/h) or in the same direction (faster than 100 km/h) as the front wheels. The system thus enables both agile and stable driving characteristics. The front-wheel steering ratio is more direct, making it easier to steer the vehicle at the limit with less steering effort.
With the aid of numerous sensors, cameras and radar, the driving assistance systems, some of which are optional, monitor the traffic and surroundings of the SL 43. The driver is supported by several new and enhanced systems that help with speed adaptation, distance control, steering and lane changes. The animated assistance display is based on a 3D scene generated in real-time. This dynamic, high-quality representation makes the operation of the driving assistance systems transparent as an augmented reality driving experience.