The new BlueDIRECT V6 engine was developed using lightweight materials consistently. It features spray-guided direct petrol injection with piezo injectors, four valves per cylinder and adjustable intake and exhaust camshafts. In addition, the energy efficiency of its auxiliary assemblies has been enhanced. The CLS 350 BlueEFFICIENCY thus saves on fuel, reduces CO2 emissions and optimises running smoothness. With an output of 225 kW, its maximum torque of 370 Nm is available at an engine speed of 3500 rpm.

The CLS 350 BlueEFFICIENCY also features the ECO start/stop function which reduces the vehicle's fuel consumption and emission levels by switching off the engine when the vehicle is at a standstill or coasting to a stop. The new operating logic causes the engine to restart automatically as soon as the driver depresses the clutch pedal fully or steps on the accelerator.

(CLS 350 CDI BlueEFFICIENCY: fuel consumption combined: 6.8 –7.0 l/100 km, CO2 emissions combined: 159–164 g/km)[1]

The newly developed BlueDIRECT V8 engine delivers effortless superiority in every driving situation. It was developed using lightweight materials consistently, in addition to which its displacement was downsized, at the same time it has been possible to reduce fuel consumption as well as the associated emission levels by 20% compared with the predecessor model.

The new-generation BlueDIRECT V8 engines boast a range of technology highlights, including petrol direct injection, two compact turbochargers for faster engine response, and an intercooler for optimised thermodynamic efficiency.

The new-generation CLS 500 BlueEFFICIENCY with BlueDIRECT engine develops an output of 300 kW and has a maximum torque rating of 600 Nm. The integrated ECO start/stop function also reduces fuel consumption when waiting at traffic lights or in a traffic jam. The function recognises when the engine is not needed and automatically switches it off.

In the CLS 63 AMG the new AMG 5.5 litre V8 biturbo engine achieves an output of 386 kW and a maximum torque of 700 Nm. This is possible thanks to a unique combination of innovative high-tech systems, including direct petrol injection, twin turbochargers, energy recuperation when braking and in overdrive mode, and the Controlled Efficiency performance setting with stop/start function. In conjunction with the AMG Performance Package, the performance figures increase to 410 kW and 800 Nm. Torque characteristics demonstrate that no other engine in this output class achieves the figures delivered by the new AMG biturbo engine.

(CLS 500 BlueEFFICIENCY: fuel consumption combined: 9.0 l/100 km, CO2 emissions combined: 209 g/km; CLS 63 AMG: fuel consumption combined: 9.9 l/100 km, CO2 emissions combined: 231 g/km)[1]