The Mercedes-Benz S-Series supercharged vehicles

Mar 10, 2014
  • 1927: Mercedes-Benz takes off with S-Series racing sports cars
  • The powerful vehicles are dubbed “ White Elephants”
  • Victory in the 1931 Mille Miglia: the first non-Italian winner
Ahead of the merger, Benz and Daimler had agreed that the racing activities of both brands would initially be continued by DMG. This was also in line with the focus on the supercharged vehicles from Stuttgart in the two years before the 1926 and after the completion of the merger. Mercedes had already been making racing cars with mechanical superchargers for some years. The most powerful of those vehicles until then was the 2-litre eight-cylinder supercharged racing car designed by Ferdinand Porsche, commonly known as the “Monza” model, because it had its race début at the Grand Prix of Italy in October 1924.
It was in one of these cars that Rudolf Caracciola won the first German Grand Prix for sports cars at the Avus track in Berlin on 11 July 1926. He completed the race distance of 392.3 kilometres at an average speed of 135.2 km/h. Because the car designed as Grand Prix car with two-litre engine started as a sports car, the body was converted by the racing department so that the vehicle formally qualified as a four-seater.
Even though the Monza racing car did not go on to play a major role in the new company’s involvement in motor sport, the first German Grand Prix did mark the beginning of a new era in motor sport: Alfred Neubauer, who saw himself more as an organiser than a racing driver from now on, developed his idea for detailed communication between drivers and the pits with a system of flags and sign boards as well as a meticulously planned process for the pit stops. In the Solitude Race on 12 September 1926, Neubauer used his sign system for the first time.
1927: Mercedes-Benz S model, the first of the “White Elephants”
The 1927 Mercedes-Benz S model touring car – the “S” stood for “Sport” – was the first supercharged sports car to be developed entirely by Mercedes-Benz for racing purposes. This further development of the K racing touring car is regarded as the first model in the series of the so-called “White Elephants”. At first glance, this was the rather unflattering nickname the racing community gave to the heavyweight vehicles from the S to the SSKL models, with which Mercedes-Benz totally dominated the racing scene in the late 1920s and early 1930s. These racing cars, painted in the white racing livery of Germany, were big, strong and powerful. But the comparison with the pachyderms ended there.
In fact, the vehicles weighing in at 1.9 tonnes with their huge engines that initially had a displacement of 6.8 litres consistently outclassed other competitors’ lighter, more manœuvrable vehicles. It was in one of these cars, featuring an improved chassis set lower than in the K model, that Rudolf Caracciola achieved worldwide fame: on 19 June 1927 at the wheel of an S model he won the inaugural race on the Nürburgring track in the class for sports cars with a displacement of over 5 litres, ahead of fellow team member Adolf Rosenberger. All in all he won eleven overall and class victories in 1927. Other Mercedes-Benz drivers were successful as well: the brand’s triumphs also included a triple victory in the German Grand Prix for sports cars at the Nürburgring over 509.4 kilometres on 17 July 1927, when Otto Merz (overall winner), Christian Werner and Willy Walb, all driving Mercedes-Benz S models, dominated the race.
In 1927, the Daimler-Benz works team entered vehicles in more than 90 races and other motor sport events. The “ White Elephants” won an overwhelming number of victories – in hill climb and touring events as well as on the racetrack. With the supercharger engaged, the six-cylinder engine of the Mercedes-Benz S model developed 132 kW (180 hp) of power at 3,000 rpm. Private motorists also wanted to benefit from this enormous power – a wish that Mercedes-Benz was happy to fulfil. These sports cars were in fact also available for non-racing customers and became the vehicle of choice for affluent motorists on public roads. While private drivers also frequently entered their supercharged cars in competitive events, the perfected racing version was reserved for the Mercedes-Benz works drivers.
1928: the Mercedes-Benz Super Sport and its successors
The engineers and designers continued to work tirelessly on further improving the outstanding design of the S model. The result of these efforts made its début in 1928 as the Mercedes-Benz SS racing touring car. The extra “S” in the name of the new top-of-the-line model stood for “Super”. The most important difference from the 1927 car was the new M 06 engine, replacing the M 9856 of the S model. The “06” in the engine model designation indicated that this engine was one of the first to be created by the joint engine development department of Mercedes-Benz. From a displacement of 7 litres it initially produced 103 kW (140 hp) of power without supercharger and 147 kW (200 hp) at 3,300 rpm with mechanical supercharger.
The standout successes of the SS model on the racetrack included the triple victory in the German Grand Prix on 15 July 1928 at the Nürburgring. The drivers were forced to take turns at the wheel because of the extreme heat. Christian Werner brought Rudolf Caracciola’s car home in first place, ahead of Otto Merz and the Werner/Walb team. Mercedes-Benz also took three victories in the 16th Semmering Race in September 1928: Karl Wenzler won the class for touring cars up to 8 litres in a Mercedes-Benz S (average speed 77.4 km/h), Ernst Günther von Wentzel-Mosau was the victor for sports cars up to 8 litres in his Mercedes-Benz SS (average speed 83.8 km/h) and Rudolf Caracciola took the competition for racing cars with a displacement of up to 8 litres in a further advanced version of the Mercedes-Benz SS. His average speed of 89.9 km/h resulted in the fastest time of the day.
The popularity of hill climb events in Germany led to the development of the SSK in 1928. The car (the extra “K” stood for “Kurz”, the German word for “short”) was technically largely identical to the SS model, albeit with a shorter wheelbase of 2,950 instead of 3,400 millimetres, and it therefore also had a shorter body. This made the SSK the perfect vehicle for the narrow mountain roads with their many switchbacks. Driving a Mercedes-Benz SSK, Rudolf Caracciola opened the 1929 racing season for Mercedes-Benz in the inaugural Grand Prix of Monaco in April with a third-place finish. That same month, he was the overall winner of the Zbraslav–Jíloviště Hillclimb race in Prague. And he also won the International Tourist Trophy in Ireland in August in pouring rain with an average speed of 117.2 km/h over 410 miles.
In the Grand Prix des Nations for sports cars at the Nürburgring, raced over 508.7 kilometres on 14 July 1929, the dominant cars were the lightweight Bugattis, which scored a one-two victory. The team of August Momberger/Max Arco-Zinneberg finished third in an SSK model. The SSK was also entered in races overseas: Carlos Zatuszek scored a string of victories in his adopted home of Argentina from 1929 onwards. And driving the SSK model, Caracciola also dominated the 1930 season for Mercedes-Benz: he won not only the Irish Grand Prix in Dublin, but also all the races he entered in the inaugural edition of the European Hillclimb Championship in the sports car class: Zbraslav–Jíloviště (in what was then Czechoslovakia), Cuneo (Italy), Shelsley Walsh (UK), Klausenpass (Switzerland), Schauinsland (Germany), Semmering (Austria), and Svábhegy (Hungary). Accordingly he was the undisputed winner of the European Hillclimb Championship.
In 1931, Caracciola started in the historically significant Mille Miglia with an SSKL, the last evolutionary stage of the SSK model. The further advanced, weight-reduced racing sports car was equipped with a 7.1-litre engine that now had a power output of 176 kW (240 hp) without and 221 kW (300 hp) with supercharger. This gave the car a top speed of 235 km/h. From the outside, the most characteristic feature of the car was the weight-saving holes drilled into various components. This measure allowed the design engineers to save a lot of weight: the holes in the vehicle frame and cross members made the SSKL 125 kilograms lighter. Nevertheless, the sports car still tipped the scales at around 1,352 kilograms.
The 1931 racing season began with a resounding success: Rudolf Caracciola and his co-driver Wilhelm Sebastian won the Mille Miglia in a Mercedes-Benz SSKL (the “L” stood for “Light”). This was the first time a non-Italian had been the overall winner of this prestigious race, which had been staged since 1927. Caracciola would later describe this Mille Miglia in vivid terms: “1,600 kilometres on dusty country roads, with ravines and steep precipices to left and right … through fearsome corkscrew and serpentine bends, towns and villages, then back to dead straight roads at average speeds of 150, 160, or 170 km/h … for a whole night and again a whole day.” The advantages the Italian drivers had seemed overwhelming: The drivers knew the roads, and since some manufacturers had entered almost 50 cars in the event, they had numerous depots with mechanics lined up all along the way. There was no way Mercedes-Benz could match such resources.
But Caracciola accepted the challenge: “For sixteen hours I sat at the steering wheel, for sixteen hours we blasted through the length and breadth of Italy, groped along the beam of our headlamps through the night, and on into the dazzling glare of a spring day.” In fact, the Mercedes-Benz lead driver crossed the finish line as the winner of the Mille Miglia on 13 April 1931: his average of speed of 101.1 km/h represented a new record. 24 years later another Stuttgart works driver would repeat this feat: British driver Stirling Moss at the wheel of a Mercedes-Benz 300 SLR.
In the 1931 season, Caracciola was however forced to race for a private team, with the factory only in a support role: the impact of the international economic crisis meant the Stuttgart-based company was no longer able to finance its own racing team. But the further advanced SSKL assigned by Daimler-Benz to its top drivers was nevertheless a trump card on the racetrack. In 1931 Caracciola also won the Eifel Race, the German Grand Prix and the Avus Race. With five victories in five starts he again won the European Hillclimb Championship for sports cars.
In the 1932 season, the Stuttgart-based company withdrew from motor sport completely because of the worsening economic problems. Rudolf Caracciola was forced to look for a new team and joined Alfa Romeo. Nevertheless, there was to be one more sensational success for the Mercedes-Benz SSKL: at the Avus Race in Berlin, private driver Manfred von Brauchitsch entered one of these vehicles that he had independently fitted with a streamlined body. The design stemmed from leading aerodynamics expert Reinhard Koenig-Fachsenfeld, and the sheet metal work was carried out by Vetter Company in Cannstatt.
Thanks to the significantly improved aerodynamics, the SSKL model, affectionately dubbed ‘the gherkin’ by the public, attained a higher top speed than the factory version and delivered a victory for von Brauchitsch. After a tense duel for the lead, the private driver won the race with an average speed of 194.2 km/h, just ahead of Rudolf Caracciola, driving for Alfa Romeo in the absence of a Daimler-Benz works team in the 1932 season. The exploits of Von Brauchitsch earned him a place on the Mercedes-Benz racing team for 1934. However, the days of the “White Elephants” as racing cars were now over. A new era was about to dawn, bringing even greater success for Mercedes-Benz than that achieved with the legendary S-Series.