1. Mercedes-Benz, the future of the automobile
2. Daimler: engines, carburetors, radiators and transmissions
3. Benz Patent Motor Car, the first automobile
4. The 35 hp Mercedes, the first modern automobile
5. Evolution of the automobile
6. Supercharged engines by Mercedes
7. From independent wheel to active suspension
8. Diesel passenger cars
9. Direct gasoline injection
10. The road to passive safety
11. Holistic accident research
12. Alternative drive systems
13. Milestones of innovation at Mercedes-Benz

Direct gasoline injection (since 1937)

Like supercharging technology and several other innovative design principles which became state-of-the-art in automotive engineering, gasoline injection for motor vehicle engines is a product of aero engine development. Hans Scherenberg, a Daimler-Benz engineer at the time, assumed responsibility for the gasoline injection project launched in 1934, and only three years later, in November 1937, large-scale production of the DB 601 A, a twelve-cylinder aero engine – the first with gasoline injection – began. It was clearly more powerful and economical than the carburetor version.

Scherenberg developed the gasoline injection system for earth-bound vehicles to production standards. The legendary Mercedes-Benz 300 SL, launched in 1954, was the world’s first production car with a four-stroke engine with gasoline injection. The Gullwing coupe with its unmistakable design was powered by a 215 hp (158 kW) six-cylinder engine for top speeds up to 260 kilometers per hour. In its final version built from 1955, the engine also featured gasoline injection, albeit in somewhat tamed form, and powered the magnificent Mercedes-Benz 300 S, launched in 1951 and the last protagonist of a legendary family of coupes and cabriolets with frames. This six-cylinder power unit generated 175 hp (129 kW) and allowed a top speed of 180 km/h.

From 1957, engine operation was determined by a new technology: gasoline injection became indirect – intermittent manifold injection, to be precise: the atomized fuel was injection into the intake manifold rather than directly into the combustion chamber. This system was first used in the Mercedes-Benz 300 d, the last of the four versions from the 300 series built until 1962.

In late 1958, gasoline injection was introduced in large-scale production. Like the 300 d, the Mercedes-Benz 220 SE, the last evolution of the 220 series launched in 1954, had manifold injection, 15 hp (11 kW) more and a much more dynamic response than its 220 S brother with carburetor – and it was even a little more economical. Specific operating parameters such as cold-starting, warm-up, intake air temperature and altitude were communicated to the injection pump by mechanical means, as electronic systems were not yet available. Compared to the carburetor engine, the manifold-injection unit boasted improved smooth-running characteristics, performance, flexibility and accelerating power. And it was easier to service. From then on, the letter “E” in the model designation was a synonym for excellent performance in Mercedes-Benz models.

The story of direct gasoline injection at Mercedes-Benz was continued at the end of 2002 with the introduction of a new 1.8-liter, four-cylinder CGI engine. CGI stands for Stratified Charge Gasoline Injection. This is the first engine in the world to utilize the potential savings of pioneering direct injection technology combined with supercharging, charge air cooling and mass balancing. It significantly reduces both fuel consumption and pollutant emissions compared to a comparable engine with manifold injection, while providing higher output and torque ratings, the smoothness of a six-cylinder engine and lower weight by virtue of its all-aluminum construction.

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