Mercedes-Benz F700 concept car created in Germany by Mercedes-Benz. It was revealed to the public at the 2007 Frankfurt motor show.
The F700 engine powered by Mercedes' DiesOtto engine, so called because it combines elements of diesel and petrol (Otto cycle). The concept engine displaces 1.8-litres, and features twin sequential turbochargers, generating 177kW and 400Nm at unspecified engine speeds. As a result, the F700 has performance equivalent to the Mercedes-Benz S350, with a fuel consumption rating of just 53 mpg.
Source: http://en.wikipedia.org/wiki/Mercedes-Benz_F700