Engines: The most efficient V8 petrol model in the luxury class

Jun 23, 2014
The two-door car is initially available with a 4663 cc V8 biturbo engine with BlueDIRECT technology. 4MATIC all-wheel drive is standard, while the rear-wheel-drive variant can be ordered from 14 July onwards.  The emotive sound of the exhaust system makes a decisive contribution to the sporty driving experience.
The V8 biturbo engine in the S 500 4MATIC Coupé has a displacement of 4663 cc  and an output of 335 kW (455 hp), making it far more powerful than its 320 kW (435 hp) predecessor. Peak torque is 700 Nm. The all-wheel-drive Coupé has an NEDC (combined) consumption of 9.4 l/100 km (premium unleaded petrol), while CO2 emissions are 219 g/km. Outstanding efficiency does not come at the cost of supreme performance: the S 500 4MATIC Coupé completes the sprint from 0 to 0 100 km/h in an impressive 4.6 seconds and goes on to reach a top speed of 250 km/h (electronically governed).
The advances in efficiency compared to the previous model are obvious: the CL 500 4MATIC model of 2008 had a much lower maximum output of 285 kW (388 hp) and provided far less torque (530 Nm) yet consumed far more fuel (12.1 l/100 km).
Stand-out features of the 90-degree V8 engine:
  • Twin turbochargers
  • The spray-guided combustion system with third-generation direct injection known as BlueDIRECT, also featuring piezo injectors and multispark ignition
  • Low component weights
  • Low mechanical power loss thanks to tribological (friction-reducing) measures at all bearing points and friction components of the barrel/piston and the control drive
  • Low fluidic and thermal power loss thanks to on-demand control of the oil circuit and ancillary components plus integrated thermal management
  • Very low NVH (Noise, Vibration and Harshness)
  • Low specific consumption and low untreated emissions
The data at a glance:
S 500 4MATIC Coupé
Number of cylinders/arrangement
Displacement (cc)
Compression ratio
max. charge pressure (mbar)
Rated power (kW/hp at rpm)
335/455 at 5250-5500
Rated torque (Nm at rpm)
700 at 1800-3500
Combined fuel consumption from (l/100 km)
Combined CO2 emissions from (g/km)
Efficiency class
Acceleration 0-100 km/h (s)
Top speed (km/h)1
1 Electronically limited
Emotive-sporty sound: exhaust system with flaps
All-new exhaust systems that meet the requirements of the current exhaust and noise emissions standards have been developed for the new S-Class Coupé.
The emotive sound of the exhaust system makes a decisive contribution to the sporty driving experience. The deeper sound components ensure a fuller, sportier sound. In the transversally positioned rear silencer of the twin-pipe exhaust system there are two flaps that can be opened and closed pneumatically depending on the engine speed.
When the flaps are open the exhaust gases are conducted through the rear silencer along a different path so that the vehicle sound becomes more powerful. The switching point of the flaps depends upon the selected drive mode - in S mode, the flaps open earlier than in E mode. As soon as the S-Class Coupé engine starts, the power of its sound can be heard.
Thermal management: two independent cooling circuits
The new S-Class Coupé has two independently operating coolant circuits. The high-temperature circuit cools the engine, cylinder head, turbochargers and exhaust gas recirculation valves, while the low-temperature circuit regulates the temperature of the charge air and the transmission. Both circuits are completely separate from each other to ensure that coolant quality is maintained over the long term.
An electronic coolant pump in the low-temperature cooling circuit performs a regulating and efficiency-enhancing function, for on-demand control of the charge-air, transmission and electronic system temperatures. An electronic regulating valve distributes the mass coolant flow as required for charge-air, transmission and electronic system cooling.
To minimise the energy required for the cooling system depending on the driving situation, fully controllable electrical components such as the electrical suction-type fan, low-temperature coolant pump and regulating valve are linked via LIN-BUS to the engine incl. turbocharger, the EGR and air intake system plus the transmission and the thermal comfort systems. Under part load with a corresponding vehicle speed, for example, the fan speed is greatly reduced, while the adaptation of the valve position and pump speed ensures that each component requiring cooling only receives as much coolant as it actually necessary to comply with the temperature limits.
Automatic transmission: outstandingly smooth gear changes as standard
The 4MATIC version of the new S-Class Coupé features the 7G-TRONIC PLUS automatic transmission with DIRECT SELECT lever. Among the traits of this latest evolutionary stage are the new torque converter with reduced slip, an ECO transmission mode with greater gear spread as well as an auxiliary oil pump that maintains the operating pressure when the engine is automatically switched off. Friction-optimised components in conjunction with low-friction oil make it possible to lower the operating pressure. The new 9G-TRONIC nine-speed automatic torque converter transmission is used in the rear-wheel-drive variants of the S-Class Coupé.