23 May 2005

Petrol and diesel technologies will be combined in to a single engine type in just a decade from now, according to Mercedes-Benz. ‘That’s our wish,’ said Dr Thomas Weber, board member responsible for research, technology and development at Mercedes-Benz. ‘Step by step, the components of diesel and petrol engines are growing closer: the combustion process, common-rail direct injection, turbocharging. In the end, we believe this development will see the complete integration of the two engines into one type which combines the best of petrol and diesel.’

Weber said Mercedes is working on such an engine, without spark plugs, that runs on synthetic fuels. It has a compression ratio somewhere between the current petrol’s (circa 10.0:1) and diesel’s (roughly 18.0:1).

Internally, the new development is known as ‘diesotto’, a word that combines the names of Rudolph Diesel and Nikolaus Otto, the two German inventors of the diesel and four-stroke Otto-cycle petrol engines respectively.

‘By combining both, the savings are huge,’ Weber said. ‘You can imagine the advantages in investment and meeting emissions. This is our vision for the future.’

Weber is convinced that only those car makers with exhaustive knowledge of the diesel process have any chance of developing something approaching the ‘diesotto’ engine. ‘The only step is to go through the diesel world,’ he said. ‘There is no chance without that.’

Weber said Mercedes’ R&D spending on petrol/diesel engines is currently split 50/50. ‘After our work on the new V6 CDi diesel (right), there is probably going to be a shift back to petrol engines,’ he admitted, citing work on second-generation, turbocharged direct-injection petrol engines that deliver a 10 per cent reduction in fuel consumption. The first of these engines is expected to hit Mercedes showrooms in 2006.

Add your comment

Log in or register to post comments

Find an Autocar car review

Driven this week

  • Skoda-Karoq 2.0 TDI 4x4
    First Drive
    16 October 2017
    Diesel version of Skoda’s junior SUV is unobtrusive and undemanding, but we’d still go for the silkier petrol version of the Karoq
  • Audi Q7 e-tron
    First Drive
    16 October 2017
    Expensive and flawed but this understated diesel-electric Audi Q7 has a lot to offer
  • Citroën C3
    First Drive
    16 October 2017
    Is the third gen Citroën C3 ‘fresh and different’ enough to take on its supermini rivals? We spend six months with one to find out
  • BMW X3
    First Drive
    15 October 2017
    A satisfying rework of the X3 that usefully improves its handling, cabin finish, space and connectivity to make this BMW a class front-runner again
  • Vauxhall Insignia Country Tourer
    First Drive
    13 October 2017
    Off-road estate is now bigger, more spacious and available with torque-vectoring all-wheel drive, but is it enough to make its German rivals anxious?