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Mercedes-Benz B-Class


This is the new Mercedes-Benz B-Class which, with new engines and transmissions, is designed to be much more efficient than the outgoing model.

It features both new petrol and diesel engines, all of which are turbocharged, as well as new manual and automatic transmissions, and an ECO start/stop function is standard on all B-Class models.

All transmissions and engines have been developed in-house, with the simultaneous development process enabling coordination of engines and transmissions; for instance, this allowed the implementation of the ECO start/stop function, which features as standard on all models.

Common features of the new drive systems are the use of state-of-the-art technologies for maximum efficiency, smooth running, high power from low revs, sustainability in terms of impending emissions standards, and low weight.

The new four-cylinder petrol engines mark the launch of a completely new engine series. The combustion process is based on the third-generation Mercedes-Benz direct injection system which was introduced last year with the BlueDIRECT V6 and V8 engines. Its use in the B-Class marks this technology’s debut in the compact segment. The new four-cylinder engines have been designed for both transverse and longitudinal installation. In the new B-Class they are initially available with a displacement of 1.6 litres, as the B 180 rated at 122 hp and the B 200 with an output of 156 hp.

The new four-cylinder diesel is a further development of the existing third-generation common rail direct-injection unit, which appears in models such as the Mercedes-Benz E220 CDI . With its displacement scaled down to 1.8 litres, this is the first time that the compression-ignition engine has been mounted transversely in a Mercedes-Benz car. The B 180 CDI generates 109 hp of power, while the B 200 CDI has an output of 136 hp.

Another Mercedes-Benz premiere is the new 7G-DCT dual clutch transmission in the B-Class. This transmission is extremely compact, extremely variable with regard to adaptation of the engine speed thanks to seven gears, features an electric oil pump for start/stop capability, shifts gear without any interruptions in tractive power, and combines the comfort of an automatic with the efficiency of a manual transmission.

The new 6-speed manual transmission designed along similarly compact lines as a three-shaft transmission is a close relative of the DCT. Easy gear shifting, low shift forces, low internal friction and a low weight are among its most important characteristics.

The electromechanical steering of the B-Class makes an important contribution to the vehicle’s overall efficiency, as the steering assist function only requires energy when steering actually takes place.

The new B-Class also has a low drag coefficient of c d = 0.26. As well as the aerodynamic exterior design, there are many detailed aerodynamic design elements such as the airflow around the front wheels, the underbody design, and the cooling airflow. Patents are pending for innovative details such as the serrated wheel arch spoiler.

The modular “Energy Space” concept means that the new B-Class is already designed to accommodate versions with an alternative drive such as electric or even hydrogen fuel cell.

The new car has lower overall height but more space inside, along with the option of the EASY-VARIO-PLUS system which enables reorganisation of the interior to enable the transportation of bulky items.

Mercedes promises that the new ‘sports tourer’ will also be more agile, helped by a 20 mm lower centre of gravity.

As a world first in the compact segment, the B-Class features a radar-based collision warning system with adaptive Brake Assist as standard, which lowers the risk of rear-end collisions. It will also come with a range of other assistance systems, including the PRE-SAFE Ž preventive occupant protection system which features in the B-Class is available for the first time in this vehicle category.

The world premiere of the new B-Class will take place at the Frankfurt International Motor Show (13 to 25 September 2011).

The car will be available in the UK in March 2012.