In 1882, Gottlieb Daimler and Wilhelm Maybach left Gasmotoren-Fabrik Deutz and thus parted with Nikolaus Otto. In Cannstatt, they proceeded to work on a high-speed four-stroke engine with a low weight. The first high-speed four-stroke engine – a small, horizontal experimental engine – was operational in 1883. It developed 0.25 hp (0.18 kW) at 600 rpm. An experimental engine with upright cylinder followed in 1884 and was named “Grandfather Clock” because of its shape.
In 1885, Daimler and Maybach fitted a scaled-down version of the Grandfather Clock into a wooden two-wheeler, the so-called riding car. In this car, the engine developed 0.5 hp (0.37 kW) at 700 rpm. The riding car was the first proof on wheels that an internal combustion engine was capable of driving a road-going vehicle that was controlled by a human being.
In 1886, Daimler installed an engine in a carriage chassis – and thus created his first automobile. The engine generated 1.1 hp (0.81 kW) at 650 rpm from a displacement of 0.46 liters; the maximum engine speed was 900 rpm. And at just 40 kilograms, this engine was light. Important steps toward the automobile had been taken.
But Daimler and Maybach also looked for a solution for a multi-cylinder gasoline engine to generate higher output. The result was the world’s first two-cylinder V-engine which powered the wire wheel car (1.5 hp/1.1 kW at 700 rpm, 0.57 liters) in 1889. The V-engine was also used for driving boats and rail-bound means of transport, and for stationary applications.
The way to the four-cylinder engine
Wilhelm Maybach was the mastermind behind numerous epoch-making inventions. In 1890, he built is first four-cylinder in-line engine with an output of five hp (3.7 kW) at 620 rpm. For the time being, however, this unit was only used as a boat engine. Maybach also continuously improved key components such as the ignition and cooling.
In 1891, Gottlieb Daimler and Wilhelm Maybach resigned from Daimler-Motoren-Gesellschaft after disputes with their other partners. They continued their development work notwithstanding, financed by Gottlieb Daimler. Maybach’s greatest feat during this time was the Phoenix engine, a two-cylinder in-line engine which was first installed in the belt-driven car in 1895 after Daimler and Maybach had returned to DMG. This engine developed an output between two hp (1.5 kW) and 7.5/eight hp (5.5/5.9 kW).
The Phoenix car with Maybach’s new four-cylinder in-line engine presented in 1898 was the world’s first road-going vehicle with such a unit. Initially, the production car had a 2.1-liter engine with an output of eight hp (5.9 kW).
Despite the high pace of innovation in automotive engineering, DMG never lost sight of other fields of application. As early as February 1899, for instance, Daimler equipped the LZ 1 airship of Count Zeppelin with gasoline engines for its maiden flight.
Controlled intake valves and honeycomb radiators
Maybach’s engine developed in 1900 for the 35 hp Mercedes again featured several innovations. Thus, the engine with six-liter displacement and an output of 35 hp (26 kW) at 950 rpm was fitted with controlled intake valves and exhaust valves. For the first time, Maybach also replaced the tubular radiator with his new honeycomb radiator in this model. The engine design of the first Mercedes also had an impact on the concept of the Mercedes Simplex models. Their four-cylinder in-line engines developed between 32 hp (24 kW) at 1200 rpm with a 5.3-liter displacement and 65 hp (48 kW) at 1200 rpm with a 9.3-liter displacement. Alongside these novel automobile engines, DMG also launched several marine engines which equally gained a firm foothold in the market.
Six-cylinder by Maybach and Paul Daimler
The final development of the ingenious design engineer Wilhelm Maybach for Daimler-Motoren-Gesellschaft was a six-cylinder racing engine in 1906. The oversquare engine (140 millimeter bore x 120 millimeter stroke) developed 106 hp (78 kW) at 1400 rpm and 120 hp (88 kW) at 1500 rpm. It was the archetype for many later engine designs, including aircraft engines.
Parallel to Maybach’s racing engine, Paul Daimler developed a six-cylinder in-line engine which powered the new 37/65 hp and 39/75 hp Mercedes models- DMG’s first production vehicles to feature six-cylinder engines. Production of sleeve-valve engines modeled on the design of Charles J. Knight began in 1910. Advantages included its quiet running and the possibility of obtaining high engine speeds of up to 1600 rpm in four-cylinder engines. In 1911, DMG introduced three-valve technology (one intake valve, two exhaust valves) as well as double ignition in the new top model, the 37/90 hp Mercedes. The engine of the 1914 Grand Prix car featured four-valve technology, however. In the latter, two intake and two exhaust valves were arranged obliquely in the countersunk roof-shaped cylinder head. This engine, with its high engine speeds (105 hp/77 kW at 3100 rpm, maximum engine speed 3200 rpm), became the prototype for aircraft engines and others. These enjoyed a good reputation, as verified, for instance, by the Mercedes DF 80, a 90 hp (66 kW) 7.2-liter six-cylinder engine which reached second place in the Emperor’s Award for the best German aircraft engines in 1913.
The supercharger era
In 1921, at the Berlin Motor Show, DMG presented the world’s first passenger car with a supercharged engine. The four-cylinder 6/20 hp and 10/35 hp Mercedes models were provided with air under excess pressure by means of a double-bladed Roots blower which generated a massive power boost. The two cars went into production in 1923 as the 6/25/40 hp and 10/40/65 hp models. They were followed by other cars with supercharged engines with four, six and eight cylinders. After the merger of Benz & Cie. with Daimler-Motoren-Gesellschaft in 1926, even the large eight-cylinder cars (380, 500 K, 540 K, 770) as well as Mercedes-Benz’s sports and racing cars likewise acquired supercharged engines. The charging not only served as a means of boosting output, but was also a characteristic of the prestigious high-performance vehicles from Stuttgart.
In December 1924, at the Berlin Motor Show, Daimler presented the new 15/70/100 hp and 24/100/140 hp Mercedes passenger car models. The two supercharged six-cylinder cars would, in future, serve as top-of-the-line models in the sales range.
The first eight-cylinder Mercedes was the two-liter Monza racing car. Its output of 170 hp (125 kW) at 7000 rpm allowed a top speed of 180 km/h.