Rudolf Diesel, inventor of the diesel engine, turns 150 this year. Or, at least he would if he hadn't died 95 years ago. To celebrate (his 150th, not the death) Mercedes has announced a new four-cylinder diesel engine set to arrive this summer.

And it sounds like a doozy. It'll first appear in the C-Class as the C250 CDI, but it's actually a 2.1-litre, twin-turbocharged unit with common-rail injection.

With 201bhp and 369lb ft of torque, it's 20 per cent more powerful than the outgoing C220 CDI... and 25 per cent less thirsty - Merc says it'll return 52.3mpg in the C-Class.

All of which makes it sound like a serious competitor for the awesome engine in BMW's 123d, which produces almost exactly the same horsepower but only 295lb of torque.

That unit will haul the 1-Series to 62mph in seven seconds flat: 0.7 seconds quicker than the C250 CDI, but the latter is a bigger car.

Merc also plans to introduce two detuned versions of the 2.1-litre diesel engine later in the year, but you don't need to concern yourself with those.

The C250 CDI will go on sale in the UK in October. Here's hoping it'll make Rudolf proud.