Smaller capacity versions of the all-alloy engine appear on other E-class and C-class models, as well as the new S-class

Mercedes claims the engine is 13 per cent more fuel efficient than the superseded in-line, 3.2-litre engine

Emissions from the engine are 50 per cent below present European and American limits

The engine features three valves per cylinder rather than the more popular four-valve layout

The Mercedes has dual ignition, which means it has two spark plugs for each cylinder

Mercedes claims using three-valve provides better emissions. It reduces exhaust gas heat loss enabling the catalytic converter to reach its optimum temperature more quickly

Dual ignition burns the fuel air mixture more efficiently than a single-plug system.

The V6 produces the same 315Nm of torque as the previous in-line engine

The torque peak comes in 850rpm lower than the old engine at 3000rpm. About 95 per cent of torque is available from 2500rpm

The engine produces 165kW, three kW more than the old powerplant

The engine has a 90-degree configuration and uses a balancer shaft in the crankcase to minimise noise and vibration

The 90-degree layout is said to be more rigid in design and installation, producing less vibration than in-line sixes

The catalytic converter reaches its optimum operating temperature within 90 seconds of a cold start

The engine mates to a five-speed automatic transmission

The E320 Elegance engine has electronic start which means the driver does not have to twist the key until the engine turns over. A brief turn is all that is needed An improved traction control system and Brake Assist, which reduces braking distances in an emergency, are part of the package

High performance Xenon gas discharge headlights are optional