“A deliciously smooth engine that can deliver
superb performance or outstanding efficiency” John Carey, Wheels Magazine
Press "Play" to view the video of the winner.
BMW’s twin-turbo 2,979cc engine appears in a variety of models, including the 335, X6, Z4 and 730.
The two-time overall International Engine of the Year winner struck a chord with the judges once again this year. Graham Johnson, Awards co-chairman, said, “BMW made a great powertrain even greater with the addition of not one but two turbo systems.”
The BMW engine is a straight six, with three cylinders supplying each turbo, thus creating a low-lag, fast-response unit. In its lower-powered guise, it supplies peak torque of 400Nm and 302bhp of power at 5,800rpm. This gives lively performance in all BMW models, with the new Z4 sDrive35i reaching 60mph in a shade over five seconds, for example.
BMW engineers point out that
the turbochargers, through their concept alone, also help to reduce overall fuel consumption levels.
For example, the turbines, made of
a special steel, are extremely resistant to high temperatures. As a result, they are able to withstand temperatures of up to 1,050°C and there is no need to increase the supply of fuel in order to obtain an additional cooling effect. This works particularly well when the engine is operating under full load.
Key to the engine’s design is
the high-precision direct injection, which has enabled a higher compression ratio to be used without risking knock.
This also means that the Z4 sDrive35i can manage average fuel consumption in the EU test cycle of 9.4 litres/100km (30mpg) and an even better 9.0 litres/100km (31.4 mpg) when the seven-speed double-clutch sport-automatic transmission is fitted to the vehicle. Specification of an aluminium crankcase helps to keep the weight down.
Arturo de Andrés from Automóvil in Spain concluded, “The amount of technology that BMW has bestowed upon this engine makes it the very best in this category.”
1. BMW 3-litre DI Twin Turbo (135, 335, X6, Z4, 730)