Mercedes-Benz 300 SL

Eternal youth is a miracle granted to only a few cars, and the Mercedes-Benz 300 SL coupé is one of this select group. The Stuttgart-based brand presented its new sports car in February 1954 at the New York International Motor Show, thereby lighting the fuse of an icon of the automotive world. With its flat, graceful body, the 300 SL had lost none of its freshness even as the millennium drew to a close and was voted “Sports Car of the Century” in 1999. The “gull-wing” doors provided that essential touch of inspiration, opening towards the sky to reveal a precisely sculpted interior. The history of the 300 SL is inextricably linked to the life of an influential admirer. It was the American importer Maximilian E. Hoffman who encouraged Mercedes-Benz to build a road car in the image of its racing coupé, and the start of production in 1954 was a sweet fruit of his efforts. The production lines said goodbye to the 1,400 units of the 300 SL coupé that were built in 1957, but the spirit of this extraordinary car lives on.

From the race track to the road

The Mercedes-Benz 300 SL was initially conceived as a racing sports car (W 194). In 1952, the coupé achieved an impressive record of success in the year's major races. At the Grand Prix in Bern, the 300 SL swept all the podium positions, an impressive performance backed up by a one-two finish ahead of a stunned field at the 24 Hours of Le Mans. The Nürburgring provided another three-peat, and Mercedes' new racing sports car also claimed victory at the Carrera Panamericana in Mexico. All of this marked a majestic return to motorsport for Mercedes-Benz, picking up where the brand had left off in a period of great success before the Second World War.

Although there were no plans to mass-produce the 300 SL at first, the words of Maximilian (“Maxi”) Hoffman were ringing in the ears of the board of directors of Daimler-Benz. The official importer of Mercedes-Benz cars in the USA campaigned tirelessly for a sports car to offer its wealthy clientele – and the racing 300 SL fit the bill perfectly. After lengthy deliberations, the green light was given for mass production of the road-going 300 SL (W 198) as well as a smaller, open-top sports car, the 190 SL (W 121).

Both models were to celebrate their premiere less than six months after the board of directors had given its approval to the project. The occasion was the International Motor Show in New York from 6 to 14 February 1954, which was at that time the most important motor show in the USA. The engineers rose to the occasion and the 300 SL and its smaller brother, the 190 SL, were ready to receive the applause of the crowd. Series production began in Sindelfingen in August 1954 and the price was set at 29,000 marks – a rather high sum at the time, especially when comparing the new model with the Mercedes-Benz 170 Vb, which sold for 7,900 marks.

The body

The body of the 300 SL was developed with the primary aim of reducing aerodynamic drag to a minimum. The result was a streamlined shape with few frills, a car that faithfully adhered to its design and has retained its freshness and charm to this day. Wonderfully proportioned and extremely dynamic, it was as if the 300 SL, moving forward on its wheels, had been cut from a single mould.

The new sports car became a real magnet for the public, not least thanks to its charismatic “gull-wing” doors. More than just a styling trick, they represented the central element of the 300 SL’s design, the ultimate example of necessity as the mother of invention. The car’s aluminium body stretched over a tubular frame which, to improve stability, was raised much higher than usual along the sides of the vehicle, making the installation of conventional doors impossible. The engineers’ response was to come up with a door concept that opened upwards. The elegance of the car’s side view was preserved by a door handle, with a discreet removable bar that unlocked the lock. The door was then opened upwards with the help of a telescopic spring.

The tubular frame of the 300 SL, designed by Rudolf Uhlenhaut, reduced weight to a minimum but provided maximum strength. A series of extremely thin tubes were welded together in triangles to produce a frame that offered impressive torsional rigidity and was only subject to compressive and tensile forces. In the standard SL, the frame weighed just 82 kilograms, while the completed vehicle in untreated condition weighed 88 kilograms. The SL 300 weighed 1,295 kilograms (2,800 lb) and the driving weight, including spare wheel, tools and fuel.

The body of the 300 SL was largely constructed from high-grade sheet steel, although aluminium was used for the engine bonnet, boot lid and door sill and door trim panels. For a relatively small extra charge, customers in the case of the SL 300 could have the body made of light alloy, which meant a reduction of 80 kilograms in the total weight of the vehicle. However, only 29 SL customers opted for this option and today their cars are highly sought-after rarities.

Technology

The technical make-up of the SL 300 owes much to the Mercedes-Benz 300 saloon (W 186 II), the favourite vehicle of many statesmen and industrialists and also known as the “Mercedes Adenauer”. The six-cylinder engine featured numerous modifications, one of which replaced the carburettor with a direct injection system – a technical advancement that was years ahead of its time. This new technology increased power to 158 kW (215 hp) and the car’s top speed to 260 km/h, depending on the rear axle ratio. Customers could choose their SL with five different ratios. The standard version, with a gear ratio of 1:3.64, was designed to offer rapid acceleration and reach 235 km/h. Gear ratios of 1:3.89 and 1:4.11 allowed even faster acceleration, while the 1:3.42 option offered a higher top speed. This figure was further increased to 260 km/h when the gear ratio was set at 1:3.25. However, this “resulted in greatly reduced acceleration, making the car less pleasant to drive in inner-city traffic,” as stated in the sales information. The 300 SL reached 100 km/h in just 10 seconds, and testers at the time measured fuel consumption averaging 15 litres per 100 km. A 100-litre fuel tank was located at the rear of the car, which could be expanded to 130 litres for an extra fee.

The engine had to be tilted 45 degrees to the left in order to fit under the extremely flat car’s bonnet, thereby reducing the amount of space in the passenger-side footwell. The SL’s centre of gravity was almost exactly in the middle of the car, which laid the perfect foundation for quick and precise cornering. The chassis was essentially the same as the 300a sedan, but with a sportier set-up, and the drum brakes were adapted in response to the increased performance of the muscular sports car. Only later, in the 1961 roadster variant, were they replaced by disc brakes on all wheels.

The interior

The interior of the 300 SL was more solid than spectacular. The standard cloth seat upholstery was available in a choice of three checkered patterns, but most customers opted for leather. Body paint came in metallic silver as standard, although red, dark blue and black were also popular.

The lack of space made getting into the 300 SL a challenge – it was a sports car, after all. Fortunately, the steering wheel could be folded down, allowing the driver to swing his legs in the direction of the pedals. Once seated, the driver enjoyed an ergonomic and refined design of the cockpit. The steering wheel was just the right distance away so that the driver's arms could reach it and the driver's feet moved intuitively towards the pedals: the 300 SL was a car designed for the driver. In addition, the instrument panel was extremely tidy and clearly arranged, with the rev counter and speedometer in the centre of the driver's field of vision, as expected.

The driving characteristics

On the road, one quickly realised why the 300 SL had been christened with those particular letters: the car was certainly sporty and light. With an engine delivering 215 hp and a total weight of only around 1,300 kilograms, acceleration was impressive, especially with the right choice of rear axle ratio. Exceptional torque guaranteed good pulling power at any speed. The steering was direct and the suspension ensured that the car adhered well to the road. There is no doubt that the 300 SL was a top-class sports car. However, it was not exactly an impractical car, as many owners quickly realized. For them, it was a high-speed touring car that offered precise driving characteristics, but did not overly drain the driver's energy. The trunk was large enough, complemented by the space provided by the rear seats. The 300 SL was also equipped with a storage compartment behind the seats for additional luggage. Customers could also order a bespoke set of luggage, designed to make the most of the available space.

How the press perceived the 300 SL

The press at the time was full of praise for the 300 SL. “Autosport” reported: “The exterior design of the 300 SL is truly wonderful and its performance almost unbelievable. The car’s construction and production quality are first class and the concept as a whole represents an uncompromising realisation of all the new ideas.” Following its initial test, “Road & Track” wrote: “We are dealing with a car whose comfortable interior is complemented by remarkably impressive driving characteristics, incredible road holding, light and precise steering and performance levels that are on par with, and even surpass, the best cars the automobile industry has to offer. There is only one thing left to say: the sports car of the future has become a reality.” And “auto, motor & sport” stated: “The Mercedes 300 SL is the most refined and at the same time most inspiring sports car of our era – an automotive dream.”

Maxi Hoffman keeps pushing

The first units of the 300 SL were sold in Europe in 1954, while Maxi Hoffman received his first customer car in March 1955. In total, 1,400 Gullwings rolled off the production line, the bulk of which – some 1,100 units – made it to the US. Hoffman had assessed the market response to the car very well and had every right to Hoffmann was pleased with his work. However, he had also succeeded in feeding the expectations of his demanding customers, who now wanted a little more comfort in their cars, a larger boot and, in many cases, a convertible version. Hoffman passed the message on to Stuttgart and once again his request bore fruit: this time in the form of the 300 SL roadster (W 198 II), introduced in 1957.

Success on racetracks and rally tracks

The racing genes of the 300 SL tempted racing drivers and privateers from all over the world to take part in sports car racing and rallying. The 300 SL made its first appearance at the popular racing events of the time in 1955 and did not have to wait long to taste success. The Mercedes-Benz 300 SL achieved legendary status long before the assembly lines came to a standstill – partly thanks to its success in racing, but above all to the captivating appeal of its impressive design. The 300 SL has been considered one of the most sought-after and highly valued cars in the world for 50 years, and its status as one of the most revered classic cars on the market will remain intact for a long time to come.

Source:

• Mercedes-Benz 300 SL
  https://emercedesbenz.com/autos/mercedes-benz/sl-class/mercedes-benz-history-the-mercedes-benz-300-sl/