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What do you think about the new generation of diesel engines which use reduced compression ratio to improve fuel consumption?

There is an article in a recent ‘Economist’ magazine on a new generation of diesel engines. These apparently achieve better fuel consumption by reducing the compression ratios, enabling lighter faster rotating engines, and improved piezoelectric fuel injectors. Mazda, Mitsubishi and Toyota are mentioned in particular as producing these engines. Are BMW and Volkswagen also making these better diesels, or do they have plans to in the near future?

Asked on 23 November 2013 by RY, Steyning

Answered by Honest John
I don't know about BMW and Volkswagen. Volvo has launched a new 2.0-litre diesel engine that emits just 99g/km CO2. Ford is certainly working on a new generation of 2.0-litre diesel engines, and GM has a very impressive new chain cam 1.6CDTI with exhaust manifold integrated into the cylinder head, following practise by Ford with its 1.0 EcoBoost petrol, PSA with its new 3-cylinder petrol, Mazda with its 2.2 Skyactiv EU6 low compression diesel (which I'm running now) and Renault with its 1.6DCI 130.

Real MPG enables you to register the fuel economy you are actually getting against your make and model of car, its engine and type of transmission.

Every time you enter an average consumption figure against your car, the overall average automatically adjusts to reflect it.

Real MPG
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