Channel 4 reports that Mercedes-Benz is going to unveil a concept car called F700, a form of luxury car at this year IAA (Internationale Automobil-Ausstellung) in Frankfurt, Germany.

The F700 will showcase Mercedes’ innovative DiesOtto engine, a turbocharged 1.8-litre, four-cylinder unit that combines diesel-style automatic ignition with a conventional petrol spark plug system on start-up and under heavy accelerative demands. This engine is capable of a 235bhp output, but with near-40mpg fuel economy.

If we still remember, at the last Tokyo Motor Show, a car named F600 Hygenius (on the picture above) was presented, a fuel-cell concept. Well, we think this F700 won’t be any different; it also showcases the latest Mercedes engine technology.

Mercedes also has said that the DiesOtto engine is suitable for use in the S-Class, so it’s a fair bet that this F700 is a preview of the next-generation luxury saloon. The company is set to unveil no fewer than 18 new models and concepts at the Frankfurt Motor Show next month; these will include the new C-Class estate, models with the new Bluetec diesel engines, and both diesel- and petrol-electric hybrids.