In the late 1970s the Federal German Ministry for Research and Technology launched the “Auto 2000” project in which several car makers participated. Fuel consumption was not supposed to exceed eleven liters per 100 km (21.3 mpg) for a vehicle with a curb weight of up to 2150 kg (4740 lbs) – a very ambitious target in those days – and the maximum for vehicles weighing 1250 to 1700 kg (2756 to 3748 lbs) was to be 9.5 liters/100 km (24.7 mpg). In addition, the car was supposed to accommodate four occupants and provide a payload capacity of more than 400 kg (882 lbs). Mercedes-Benz met the requirements.
“Auto 2000,” first presented to the public at the 1981 Frankfurt International Motor Show, had an aerodynamically optimized body with a very low Cd (drag coefficient) of 0.28. As many as three different engine concepts were tested in this vehicle. Automatic cylinder cutoff premiered in a V8 gasoline engine displacing 3.8 liters. When little power was required, four of the eight combustion chambers were temporarily shut down – today this is a feature of several large-displacement gasoline engines from Mercedes-Benz. The 3.3-liter diesel engine tested in “Auto 2000” had exemplary accelerating power owing to six cylinders and two turbochargers and excelled with a consumption of 7.5 liters per 100 kilometers (about 31.3 mpg) at a speed of 120 km/h (75 mph).
With the third drive unit of the “Auto 2000,” the engineers realized an ambitious project: the automotive gas turbine. It had several qualities, including low-pollutant combustion, low weight, compact dimensions, favorable torque characteristics, and the elimination of water cooling. All engines were harnessed to a four-speed automatic transmission.
A gas turbine was used as a third variant, initially developing 94 kW (128 hp), and later 110 kW (150 hp). The two-spool turbine ran on diesel fuel and was developed using ceramic materials. It successfully completed its initial trial run in May 1981.
The fact that it was able to run on different types and qualities of fuel was another advantage for use in motor vehicles. However, although the results were promising, development proved a dead end because of the narrow range within which the gas turbine could operate efficiently at the contemporary state of the art.
Unfortunately, many such research commissions result in a dead end. At the same time, there is almost an equal number where the opposite is the case, where research is successful and the result is a great invention that changes everyday technology and the people’s lives. Because of the uncertainty of the outcome, research always requires a degree of daring to get underway. In the case of a business enterprise, for example, this is reflected in the budgets provided for the research departments, and also in the degree of independence given to all the staff who work there. The innovation history at Daimler AG in the field of alternative drive systems clearly shows that the right approach brings great dividends. After all, this is the only way that the automobile can be constantly improved.
Also, integral seats for the driver and front passenger, with all the belt mounts on the seat itself, were tested in “Auto 2000,” along with integral child restraint systems in the rear and pedestrian-friendly bumpers.