SL-Class

Mercedes-Benz History: The Mercedes-Benz SL-Class W121 Series 1955 to 1963

Words Jim Davis | March 30, 2010
First, series production of the Mercedes-Benz 300 SL began in August 1954 at the Sindelfingen plant
Words Jim Davis March 30, 2010

The story of the Mercedes-Benz 190 SL starts with Maximilian Hoffman. He was the Mercedes-Benz brand’s official importer for the US market in New York since 1952. When the company presented him two ideas in early September 1953 – bring the 300 SL racing sports coupé (W 194 series) as a production vehicle and simultaneously team it up with an open-top touring sports car – he recognised the potential for sales in the USA.

At the time, however, Daimler-Benz was completely absorbed in other design and development activities – for production vehicles and also for the 1954 racing season, for which the new formula racing car of the W 196 R series was earmarked. The pressures of work even made the Stuttgart people put off their plans to participate in sports car racing in 1953. So the new SL models increased the pressure, but they were important for the image of Mercedes-Benz – the 1950s marked the beginning of a new era after the Second World War. And these were interesting cars too because Mercedes-Benz lacked sporty vehicles in its range. Already in mid September 1953, the Board of Management made a decision: the road version of the 300 SL (W 198 I) would come out along with a smaller, open-top sports car, the 190 SL (W 121).

About five months after the decision the touring sports car and the super sports car were to celebrate their premieres – in America, at the International Motor Sports Show in New York, taking place there from 6 to 14 February 1954. At the time it was the most important motor show on the other side of the Atlantic. This meant that the engineers had very little time for development. So they had to hurry: a few days after the Board’s decision to build both vehicles, the directors of Daimler-Benz were examining the first sketches, and two weeks further on they were able to assess the first 1:10 scale model, which was followed eight weeks later by a full-scale model. And the pace of development was raised still further. The floor assembly, which came from the Mercedes-Benz 180, had to be adapted to the new ideas and the right engine had to be found. Moreover, the tight time schedule stipulated that the contours of the planers on which the body would be created be finalised by 31 October 1953.

The race against time was won: Mercedes-Benz registered a tremendously favourable response to both vehicles at the show.

Up until then, the bodies of various models also were available in the two-seater A-version as Cabriolet, Roadster or Coupé, the most recent example being the Mercedes-Benz 220 Cabriolet A (W 187). According to chief engineer Fritz Nallinger, this body variant would be replaced in future by the SL vehicles – no longer with the existing formal lines and face and explicitly in the SL design, including the star placed centrally on the radiator grille – a paradigm change in the model structure. The 190 SL was thus the symbol of a new product philosophy and the forefather of the SL-Class.

First, series production of the Mercedes-Benz 300 SL began in August 1954 at the Sindelfingen plant. The 190 SL, on the other hand, was thoroughly revised once more because the car displayed at the International Motor Sports Show in New York was neither technically tested nor stylistically mature. In March 1955 Daimler-Benz then presented the final model of the touring sports car at the Geneva Motor Show. The body was designed by Walter Häcker and closely followed the design of the Gullwing Coupé 300 SL, but unlike the 300 SL the 190 SL had a retractable soft top. The production body showed some clear differences from the show car: the stylised intake scoop on the bonnet was dropped; the forward edge of the bonnet had been moved farther back; there were “eyebrows” above the rear wheel cut-outs too; and the bumpers, indicators and tail lights were modified. The Sindelfingen factory built the pre-production series starting in January 1955. Standard production commenced in May.

A body all in the style of the 1950s

The 190 SL is technically related to the “Ponton” (pontoon) saloons – commonly called that because of their characteristic body shape – of the W 120/121 series. Internally they were designated W 121, and the 190 that appeared in 1956 also got that designation. From the beginning the 190 SL was designed as a two-seater cabriolet.

In the 1950s the meaning of the term “roadster” changed. The classic roadster is a rather spartanly appointed sporty two-seater having detachable side windows, for instance, and a removable fabric top cum roof frame. But the customers’ comfort standards now were higher, and the touring sports car Mercedes-Benz 190 SL made allowance for this. Though not a roadster in the classic sense, it was interpreted as that by the company.

In contrast to the 300 SL it was not conceived as a pure-bred sports car, but a sporty, elegant two-seater touring and utility car. It was available in three versions: a car with a fabric top (price in February 1955: DM 16,500) and a coupé with removable hardtop, optionally with or without a fabric top (price in September 1955: DM 17,650/DM 17,100). For comparison: the 300 SL cost DM 29,000 DM in 1954, and the 180 Saloon had a list price of DM 9450 in 1954/1955. As an optional extra a third seat could be fitted in the rear, at right angles to the direction of travel.

The motor press praised the 190 SL among other things for its safe handling properties. They were ensured by the low-pivot single-joint swing axle already familiar from the 220a, and other features. The front wheel suspension including the subframe was adopted from the 180, from which the floor assembly – though shortened – also came.

A new development was the 1.9-litre petrol engine with the number M 121 B II. The four-cylinder unit has a single overhead camshaft and is regarded as the progenitor of an entire family of engines. In the Mercedes-Benz 190 SL it developed 77 kW at 5700 rpm and accelerated the fabric-topped variant from 0 to 100 km/h in 14.5 seconds. The top speed was a respectable 170 km/h – it made it one of the fastest cars on the road in the 1950s and 1960s. The petrol consumption was put at a rather moderate 8.6 litres; the 65-litre tank provided adequate range.

During its production period the 190 SL underwent many improvements in details. Clearly recognisable are the wide chrome strips on the upper edge of the door (introduced in March 1956) and larger tail lights (June 1956, as also used on models 220a, 219 and 220 S). In July 1957 the rear licence plate lamp was moved to the bumper horns to enable fitting the wide licence plates which were being introduced at the time. The rear bumper horns were thus a basic equipment item, while at the front they cost extra; the US versions always had them at the front and the rear as standard. From October 1959 a new hardtop with a larger rear window gave the coupés much improved rear visibility. In August 1960 the lock of the boot lid was changed; simultaneously a recessed handle replaced the previous bow-type handle. In 1963 the last Mercedes-Benz 190 SL rolled out of the production bay. In all, 25,881 were built. Most of them went to the USA – Max Hoffman’s calculation proved right.

A sports variant of the Mercedes-Benz 190 SL

The first sales brochures showed a sports variant of the 190 SL: light-alloy doors, small Perspex racing windscreen, no soft top, no bumpers, heat exchanger or insulating material, gave it a weight of 1000 kilograms, around ten percent less than the normal road version. The number of units built is not documented, and few sports versions found their way to the customers; they probably also came in for further fine tuning with modifications to the four-cylinder engine, lowering of the body, sports shock absorbers and modified springs. The sports 190 SL scored its biggest success in 1956 in the Sports Car Grand Prix in Portuguese Mação, entered by the then Daimler-Benz importer in Hong Kong. The right-hand-drive sports car took first place ahead of a Ferrari Mondial and various Jaguar and Austin-Healey cars. In the same year the Mercedes-Benz general importer in Morocco won his class (GT to two litres displacement) in the Grand Prix of Casablanca. On account of the racing regulations the idea of the sports 190 SL was not pursued any further: in many competitions the vehicle, modified as described, would have been classed as a production sports car and thus would not have had a chance. On top of that a decision of the racing authority FIA (Fédération Internationale de l’Automobile) prevented classification as a GT – it said that a Gran Turismo must have a completely enclosable body – a condition which the converted 190 SL could not meet.

The Mercedes-Benz 190 SL in the press

Shortly after the presentation of the Mercedes-Benz 190 SL at the International Motor Sports Show in New York, auto motor und sport, Germany, No. 3, 1954, wrote: “The Mercedes 190 SL is an elegant and fast touring sports car that can be used as an ordinary, workaday vehicle, but additionally offers the possibility of successfully competing in smaller sporting events. … For this new model Mercedes dispensed with its hallowed radiator tradition, as it did for the 300 SL. The very harmonious front end nevertheless shows that elegant and distinguished lines are entirely possible without neglecting the attributes of fashion and functionality.”

In 1960 auto motor und sport, Germany, No. 15, 1960, published a detailed test report on the Mercedes-Benz 190 SL: “The 190 SL owes its good reputation not just to its elegant appearance, but also to its robustness and reliability and its accurate handling. The good build quality of the body and the roadster soft top deserve special mention.”