January 17, 2008 - Talk about making an entrance – the smart fortwo and the Mercedes-Benz E-Class travelled 4400 kilometres over seven days from Los Angeles to the Detroit Auto Show. In the trip, which aimed to measure fuel economy in real world conditions, the smart fortwo mhd recorded an average fuel consumption of 4.8 litres per hundred kilometres, the two smart fortwo cdis recorded 3.9 L/100 km, and the business saloon E 320 BLUETEC recorded 5.8 L/100 km.

The fortwo models drove through highways, deserts, mountain passes and busy cities in snowy conditions that saw temperatures sink down to -15 degrees Celsius.

The average North-American mid-size car travels at a fuel efficiency of 9 L/100 km over highways and 11 L/100 km through cities. With its 52 kW/71 bhp 1 litre petrol engine, the smart fortwo micro hybrid drive (mhd) showed that consumption of less than 5 L/100 km can be achieved as a real on-the-road figure. The reduction in gas guzzling is due to a new, sophisticated start-stop function that uses the idling phases to completely shut down the engine – for example at traffic lights, level crossings or in stop-and-go-traffic. As soon as the driver releases the brake pedal the engine starts automatically and the journey can continue immediately without a perceptible delay.

On Route 66 the smart fortwo cdi proved that it rightly deserves the distinction of being the most economical production car with a combustion engine. Thanks to the world's smallest direct injection diesel engine, the 33 kW/45 bhp two-door model consumed just 3.9 litres per 100 kilometres and travelled approximately 850 kilometres without refuelling. The record still falls short of the Volkswagen Lupo, which achieved a fuel efficiency of 3 L/100 km, but is no longer in production.

Mercedes-Benz launched the E 320 BLUETEC in 2006, and the modular emission control system makes it the world’s cleanest diesel, and undercuts all international emission limits. On the road trip to Detroit, its 165 kW/224 bhp three litre V6 engine proved to be at least as economical as a four cylinder engine in everyday use, with an average consumption of 5.8 l/100 km. A European version of the E 320, named the E 300, is now available to customers in certain markets. The petrol version of the environmentally friendly smart fortwo will be available in the USA from this month.

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