Mercedes-Benz is pressing ahead with its efficiency drive: seven new versions of the A, B and CLA-Class now offer fuel savings of up to 7 percent compared with their respective predecessors. The A 200 CDI 4MATIC and A 220 CDI 4MATIC additionally represent the first all-wheel-drive diesel models forming part of the new generation of compact cars from Mercedes-Benz. All models are available to order now, with deliveries set to begin in March 2014.
With combined fuel consumption of 5.4 litres per 100 kilometres and corresponding CO2 emissions of 125 g per kilometre, the CLA 250 sets new standards in its segment. Compared with the previous model, the reduction in the fuel consumption of the 155 kW (211 hp) Coupé represents a saving of 9 g of CO2 per kilometre, or 7 percent. This drop in fuel consumption has been achieved by means of a lean-burn process with stratified-charge operation.
A 200 CDI will have a displacement of 2.2 litres at its disposal in future, as opposed to the previous 1.8 litres. It retains a rated output of 100 kW (136 hp) and maximum torque of 300 Nm, and emits only 102 g of CO2 per kilometre with the 7-speed DCT – 7 g less than its predecessor. This corresponds to a fuel consumption figure of only 3.9 litres per 100 kilometres. In addition, the A 200 CDI already complies with the Euro 6 emissions standard. The top diesel models in the guise of the A 220 CDI, B 220 CDI and CLA 220 CDI have also been revamped. In-engine optimisation measures have resulted in a further reduction in fuel consumption – as standard and with the same performance data.
The new A 200 CDI 4MATIC and A 220 CDI 4MATIC models offer efficiency combined with traction, as the first all-wheel-drive diesel models in the new generation of compact cars from Mercedes-Benz. The most innovative components of the new 4MATIC include the power take-off to the rear axle, which is integrated into the 7G-DCT automated dual clutch transmission, and the rear-axle gear unit with integrated, hydraulically actuated multi-disc clutch. This set-up allows fully variable distribution of the drive torque between the front and rear axles. Additional benefits of this design are a lower system weight compared with the competition and also high efficiency.
All models are available to order now and will be dispatched to the dealerships from March 2014.
CLA 250: lean-burn process with stratified charge operation
The CLA 250 sets new standards with combined fuel consumption of 5.4 litres per 100 km (125 g of CO2 per km). The 155 kW (211 hp) four-door coupé generates maximum torque of 350 Nm, which is available throughout the wide range of 1200 to 1400 rpm. It accelerates from 0 to 100 km/h in a sporty 6.7 seconds.
The four-cylinder engine of the new CLA 250 is a member of the BlueDIRECT family of petrol engines. It is operated in stratified or homogeneous mode, depending on the operating state. In stratified charge mode, the high-compression engine operates with a high level of excess air. To this end, the fuel is not injected into the air until the compression phase, after the air has been compressed by the pistons. A precision-controlled electronic multiple injection process ensures that a fuel-air cloud localised in the area of the spark plug forms only at the time of ignition.
This fuel-air cloud is ignited by the spark plug and in turn ignites the very lean mixture which is distributed throughout the rest of the combustion chamber. This enables extremely efficient combustion with a high level of excess air. A prerequisite for stratified charge operation is fast piezo injectors. These spray the fuel into the combustion chambers several times in succession per power stroke, and as such enable specific control of the mixture formation and thus the flammability.
A lowered comfort suspension is now additionally available for all CLA models – optionally in conjunction with the Urban equipment line, AMG Line and the CLA 180 BlueEFFICIENCY Edition.
A 200 CDI: compliance with the Euro 6 emissions standard
The engine of the A 200 CDI now has a displacement of 2.2 litres as opposed to 1.8 litres, the maximum output stands at 100 kW (136 hp) and maximum torque of 300 Nm is available. This engine incorporates numerous efficiency-boosting measures. These modifications include optimisation of the belt drive, a cylinder head package with different roller bearings and additional finishing, optimisation of the vacuum pump, aluminium pistons with optimised assembly clearances and a low-friction ring package, the roller bearings of the Lanchester balancer shaft and pressure sensor combustion control in the cylinder head. At 3.9 litres of diesel per 100 kilometres (102 g of CO2 per km in conjunction with the 7-speed DCT), its combined fuel consumption is outstanding for this power category. In addition, the A 200 CDI already complies with the Euro 6 emissions standard.
