Mercedes-Benz is introducing new V6 and V8 gasoline direct injection engines for the CL and S Class that increase output by as much as 12.5% and decrease gasoline consumption by as much as 24%. Central to this enhanced efficiency is the newly developed BlueDIRECT technology with third-generation spray-guided gasoline direct injection in combination with a standard-fit start/stop function and the new the friction-optimized 7G-TRONIC PLUS seven-speed automatic transmission featuring new torque converter technology.
The new V6 and V8 power plants for the luxury saloons and coupés from Mercedes-Benz establish a modular and flexible gasoline engine family. Depending on configuration, both engines operate with or without turbocharger and can be combined with 4MATIC all-wheel drive and hybrid modules.
S 350 BlueEFFICIENCY. The new S 350 BlueEFFICIENCY with V6 engine consumes 7.6 liters of premium gasoline per 100 kilometers (31 mpg US) in the NEDC, with corresponding CO2 emissions of 177 g/km. The previous model offered 10.0 L/100 km (23.5 mpg US) and 234 g/km CO2.
The design highlights of the 3.5-liter V6 in the S 350 BlueEFFICIENCY include a completely new air intake and exhaust system in conjunction with a variable resonance intake manifold and optimized inflow and backflow. Result: with the same displacement, the output compared with the previous 200 kW (272 hp) model rose by 12.5% to 225 kW (306 hp), while maximum torque has increased by 5.7 percent to 370 N&iddot;m (273 lb-ft) (predecessor: 350 N&iddot;m) and now is available over a broad engine speed range from 3500 to 5250 rpm.
The V6 engine is naturally aspirated, but it is suitable for the future use of a turbocharger. The new V6 unit features a reduction in the V-angle between the cylinder banks from 90 degrees to 60 degrees. This enables the primary balancer shaft to be omitted.
S 500 BlueEFFICIENCY. The new V8 biturbo engine in the S 500 BlueEFFICIENCY and CL 500 BlueEFFICIENCY generates 320 kW (435 hp) with 15% less displacement (4663 instead of 5461 cc), getting around 12% more power than its 285 kW (388 hp) predecessor. Torque rose from 530 to 700 N&iddot;m (516 lb-ft)—an increase of 32%.
Despite substantial extra power, the Mercedes developers were able to cut the combined fuel consumption of the S 500 BlueEFFICIENCY noticeably. At 9.4 liters of premium petrol per 100 kilometers (25 mpg US), fuel economy is 15.5% (short wheelbase) and 16% (long wheelbase) better than in the previous model. This is equivalent to CO2 emissions of 219 grams per kilometer.
BlueDIRECT. The centerpiece of the BlueDIRECT technology package is the improved third-generation direct injection with spray-guided combustion and piezo injectors. In combination with multi-spark ignition it taps further possibilities for improving consumption—in the V8 unit through a further developed homogeneous combustion process (“homogeneous split”); in the V6 engine through a new stratified combustion method with a much larger useful engine characteristic map and lean-burn combustion for optimum consumption (“homogeneous stratified mode”).
As the name indicates, the HOS method is a combination of homogeneous-lean and conventional stratified combustion. The first injection takes place during the intake stroke so that a homogeneous base mixture is formed. The stratified injection proper takes place during the compression stroke prior to ignition, as map-controlled single or double injection.
Combining start-stop technology, shift point adjustment and thorough reduction of friction losses, the Mercedes developers have achieved improvements in road consumption of more than 20%.In addition they have reduced the power consumption of the engine accessories.
Among other things, the S 350 BlueEFFICIENCY and S 500 BlueEFFICIENCY get an optimized water pump with second-generation thermal management, a demand-controlled oil pump, a volume-controlled high-pressure fuel pump and an intelligent alternator management system with braking energy recuperation.