Page 6 of 94 Cylinder Diesel: Introduction
BMW’s new four-cylinder diesels displace 2.0 litres cubic capacity and come in three power and performance stages: Both the “basic” model developing 105 kW/143 hp maximum output and the 130 kW/177 hp version come with a turbocharger featuring variable turbine geometry for superior power and performance. The most powerful version of the new engine also boasts Variable Twin Turbo technology already lauded in BMW’s six-cylinder diesel models. This technology also referred to as multistage turbocharging gives the 2.0-litre power unit maximum output of 150 kW/204 hp, making this the first all-aluminium diesel engine in the world to develop output of more than 100 hp per litre.
The new diesel concept is integrated within a network of improved components around the engine serving to minimise fuel consumption and emissions and optimise management of the engine’s ancillary units.
On all models driven by a new-generation four-cylinder diesel Brake Energy Regeneration, an Auto Start Stop function and a gearshift point indicator for manual gearbox cars as well as new electrical power steering serve to enhance efficiency to an even higher, unprecedented level.
Development strategy for EfficientDynamics consistently implemented.
Introducing the new four-cylinder diesel engines, BMW is implementing the development strategy for EfficientDynamics consistently also in this drive segment. Compared with the former power units, the new engines are significantly lighter and offer a substantial improvement of both fuel economy and emission management despite their considerable increase in power and performance.BMW’s new four-cylinder diesel engines are featured in a number of model series, ensuring that trendsetting innovations in technology for the enhancement of efficiency are available to the customer in several car segments with a particularly high volume of sales. Customers opting for diesel power thus benefit for the first time in both the four- and six-cylinder segment from supreme engine technology offering the highest standard of power and performance plus equally superior economy. A further advantage particularly of BMW’s modern diesel engines is the significant reduction of CO2 emissions.
As a result of all these strengths, BMW’s highly appealing new four-cylinder diesels make an important contribution to the overall reduction of fuel consumption and emissions.
The engines in BMW’s new generation of four-cylinder diesels develop their superior power from a capacity of 1,995 cc and come in three power and performance stages. Their distinction lies in the specific modification of the injection components and the turbocharger system. Developing maximum output of 105 kW/143 hp and peak torque of 300 Newton-metres/221 lb-ft, even the “basic” version of the new diesel outperforms its predecessor by 15 kW/20 hp and, respectively, 20 Nm/15 lb-ft.
The most powerful version of the new engine develops maximum output of 150 kW/204 hp, 30 kW/41 hp more than the formerly most powerful four-cylinder diesel from BMW – and at 400 Nm/295 lb-ft, the engine’s peak torque is up by 60 Nm or 44 lb-ft. The middle engine in the four-cylinder diesel range is a 130 kW/177 hp power unit developing maximum torque of 350 Nm or 258 lb-ft.
Another important factor clearly confirming the extra temperament of the engines is the engine speed band approximately 10 per cent broader than before. Hence, the superior pulling force from low engine speeds so typical of a BMW diesel is now combined with even faster and more dynamic revving characteristics.
This impressive enhancement of engine dynamics comes hand-in-hand with an equally impressive optimisation of all-round economy. In practice, this means that fuel consumption by the new BMW 118d in the EU test cycle is down by approximately 16 per cent versus the former model to a mere 4.7 litres/100 kilometres or 60.1 mpg Imp – despite an increase in power by 15 kW to 105 kW/143 hp. The new BMW 120d, in turn, comes with an increase in output by 10 to 130 kW (177 hp) and an improvement in fuel economy of the same magnitude, the engine now making do with just 4.9 litres of diesel fuel/100 kilometres (equal to 57.6 mpg mp).
Impressively reaching even the most ambitious targets.
In developing the new family of diesel engines, BMW’s engineers sought from the start to enhance both output and torque while at the same time optimising the weight of the engine and reducing fuel consumption significantly versus the former power units. So it is precisely these features that characterise the BMW Group’s development strategy for EfficientDynamics, with the new four-cylinder diesels impressively fulfilling all of these requirements.
For reasons of production technology and efficiency, BMW follows the principle to build four- and six-cylinder diesel engines of the same size (displacement) but in different power configurations. So looking at the new generation of four-cylinders, this means that the 2.0-litre has been developed in no less than three different versions.
All-aluminium crankcase for optimum engine weight.
Both the “basic” and the top engine significantly outperform their predecessors in terms of both output and torque. And at the same time the new engines are 17 kg or more than 37 lb lighter than the former-generation four-cylinder diesel. This optimisation of weight has a positive impact not only on the car’s all-round economy, but also on the harmonious distribution of axle loads. And this, in turn, means improved agility in the models driven by BMW’s new four-cylinder diesels.
In terms of both economy and emissions, therefore, and in the area of driving dynamics, the new engines stand out clearly as the leaders in their respective segments.
The starting point for developing BMW’s new family of engines was the successful four-cylinder diesel with the same size as the new power units, developing 90 and, respectively 120 kW (122 and, respectively, 163 hp) in its former configuration. To take the extra power of the new engines into account, the diameter on the main bearings on the crankshaft has been increased accordingly. A further point is that in parallel to the increase in power, engine weight has been significantly reduced mostly by the new aluminium crankcase with its thermally bonded grey-cast iron bushes taking the place of the grey-cast iron block used so far.