In December 2011, Mercedes-Benz announced the all new SL-Class and was formally launched at the North American International Auto Show in January 2012. The new SL (R231) has been produced for the first time almost entirely from aluminium. The new aluminium bodyshell weighs around 110 kilograms less than it would using the steel technology from the predecessor. Although the Mercedes-Benz SL-Class has more assistance systems on-board than its predecessor and therefore does actually sacrifice some of the weight saved through the aluminium bodyshell, the scales show some better figures: the SL 500 (1,785 kg) weighs around 125 kilograms less and the SL 350 (1,685 kg) is 140 kilograms lighter than its predecessor.
New features include the unique FrontBass system (it uses the free spaces in the aluminium structures in front of the footwell as resonance spaces for the bass loudspeakers) and adaptive windscreen wipe/wash system MAGIC VISION CONTROL, which supplies water from the wiper blade as required and depending on the direction of wipe. The R231 is also available with two different suspension systems: semi-active adjustable damping as standard. The optional active suspension system ABC (Active Body Control) is available as an alternative. Both suspension variants are combined with a new electromechanical Direct-Steer system featuring speed-sensitive power steering and a ratio that can be varied across the steering wheel angle and it also reduces the amount of steering required when parking and manoeuvring.
The 1990 Mercedes SL base model was the 228 hp (170 kW) 3.0 L inline 6 300SL version in the US. In Europe the base model was the 190 hp (140 kW) 3.0 L inline 6 300SL with 12 valves, and the 228 hp (170 kW) 3.0 L inline 6 with 24 valves is known as the 300SL 24 . But it was the 322 hp (240 kW) 500SL (with a 5.0 L V8 engine) which made the most headlines. The specification was high, with electric windows, mirrors, seats and roof.
The 300SL was introduced in 1954 in coupé form, featuring gullwing doors. The 300SL roadster succeeded the coupé in 1957. The 4-cylinder 190SL was more widely produced with 25,881 units, starting in 1955. Cars of the open SL-Class were available as a coupe with a removable hardtop or as a roadster with convertible soft top or with both tops. Production for the 190SL and 300SL ended in 1963.
TEXT FROM WIKIPEDIA - MERCEDES SL500