New generation of V-engine brings more Power, Efficiency and Refinement

The new Mercedes-Benz V-engine family is based on modularisation and allows the use of a start/stop function, 4MATIC all-wheel drive and combination with a hybrid module. It also provides the base for future development, especially of the hypotethical the twin-turbo V6. With its new-generation V-engines, Mercedes-Benz is clearly demonstrating that with concerted further development, internal combustion engines still have a great deal of potential.

For start, the naturally aspirated V6 engine develops the power of 225 kW / 306 hp (previously 200 kW / 272 hp) and torque of 370 Nm (a 20 Nm increase), available between 3500 and 5250 rpm.

This engine is being designed for better fuel efficiency. Inside the Mercedes S350 it burns one quorter less petrol, measured in the combined cycle (7.6 l / 100 km) by the use of a start/stop function as standard and other features such as newly developed, third-generation direct petrol injection with spray-guided combustion, multiple injection and multi-spark ignition.

The new V6 engine has the potential for future turbo aspirated application, thanks to the modular design concept applied to both the V6 and the V8. The most striking change between the new V6 unit and its predecessor is a reduction in the V-angle between the cylinder banks from 90 degrees to 60 degrees. This enabled the balancer shaft countering primary vibrations to be omitted, and as a result the driver registers an outstanding level of comfort.

A completely new intake and exhaust gas system with a variable-resonance intake manifold and optimised airflows was also developed for the new V6.

The high-tech V8 bi-turbo engine brings new levels of efficiency to the premium segment, despite a bit of downsizing applied to it. The result is an outstanding power delivery at low engine speeds, together with smoothness and refinement that is remarkable even for an eight-cylinder.

The V8 will debut in the CL-Class coupe, and later in the S-Class from autumn 2010. Inside the 2007 CL 500 4Matic (CL550 4Matic in America), the old 5.5-litre V8 engine (285 kW) consumes 12.3 litres per 100 kilometres and this new V8 engine will make the figure drop to 9.5 litres. That’s a useful 22 percent reduction of fuel consumption, which reflects to CO2 emissions too (reduction from 288 g/km to 224 g/km).

The new V8 with 15-percent smaller displacement (4663 cc rather than 5461 cc) develops 12 percent more power (320 kW / 435 hp instead of 285 kW/388 hp) and 32-percent higher maximum torque.

Two turbo units provide 700 Nm of torque (530 Nm previously), which is now available at lower speeds and spread across a wider range of engine speeds. Compared to the previous engine, paired turbos increase the torque figure more than 40 percent at 2000 rpm. An outstanding 600 Nm is available between 1600 and 4750 rpm. The driver therefore perceives no turbo delay, but experiences the same pleasant and effortless performance from the new V8 as that delivered by a mighty, naturally aspirated 7-litre engine. The 4,7-litre V8 will eventually replace the current 6.2-liter normally-aspirated V8 throughout the lineup.

Mercedes will use a 536 hp and 563 hp versions of this new V8 (M157) inside the new S63 AMG, and at that time, the number 63 will not mean 6.3 litres any more.

What's common for the V6 and V8?

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 that are unique in this combination:
• In combination with multi-spark ignition, a further developed, third generation direct fuel 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 percent are possible.
• Power consumption by ancillary units has been reduced. These include an optimised water pump with 2nd-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.

With its new-generation V-engines, Mercedes-Benz is clearly demonstrating that V6 and V8 engines with their high level of refinement can continue to be used to good effect in the future.