New V-Engine Generation from Mercedes-Benz Feature 3rd Generation Gasoline Direct Injection and New Operating Modes for More Power and Torque and Lower Fuel Consumption

The new V6 engine. Click to enlarge.

Mercedes-Benz is introducing its newly developed V-series (V6 and V8) engines. The new V engines offer more power and torque, and 22-24% lower fuel consumption than their predecessors.

Mercedes-Benz has achieved this increase in efficiency through the use of a technology package that incorporates third-generation direct gasoline injection with spray-guided combustion, multiple injection and multi-spark ignition; new operating modes; the use of a new start/stop function as standard; and other features.

The new V8 engine. Click to enlarge.

Both the new V6 and the new V8 from Mercedes-Benz have aluminium crankcases, pistons and cylinder heads. The crankshaft, connecting rods and valves are of special forged steel. The technology package in the new engine generation includes a number of new developments:

• In combination with multi-spark ignition, a further developed, third-generation gasoline direct injection system with spray-guided combustion and piezo-electric injectors offers further possibilities for fuel savings—in the V8 by means of an improved, homogeneous combustion process, and in the V6 by a new, stratified combustion process with a considerably extended characteristic map and fuel-efficient lean-burn technology.

• In conjunction with start/stop technology, shift point adjustment and specific friction-reducing measures, improvements in day-to-day fuel consumption by more than 20% are possible.

• Power consumption by ancillary units has been reduced. These include an optimized water pump with 2^nd-generation thermal management, a demand-controlled oil pump, a volume-controlled high-pressure fuel pump and an intelligent generator management system.

• Lightweight construction techniques and detailed improvements have also reduced in-engine friction considerably compared to the previous engine.

Direct injection system. The system pressure is up to 200 bar, the pressure being variably optimized according to the engine’s characteristic map. Completely newly developed piezo-electric injectors allow up to five injections per intake stroke for optimal mixture formation.

The piezo-electric injector has a response time of 0.1 milliseconds, allowing the fuel injection to be very sensitively and precisely adjusted to the current load and engine speed, with a beneficial effect on emissions, fuel consumption and combustion noise.

The multiple injections even in tiny quantities made possible with piezo-electric injection technology were used by Mercedes-Benz engineers to control a wider characteristic map with the efficient lean-burn process, and to provide the conditions for further functions.

New operating modes. As the first new operating mode, Mercedes-Benz engineers have developed “Homogeneous stratified combustion” (HOS). HOS is a combination of homogeneous lean-burn and classic stratified combustion