part of a whole new family of engines
Mercedes rolls out new generation V8, inline 6 and 4 cylinder engine
Cristi Stefan , October 29, 2016
Mercedes-Benz reveals its plans and tech for an all-new generation of powerpants, including a potent new twin-turbo 4.0L V8, new in-line 4 and 6 cylinder engines and various clever new tech, starting with a new 48V electrical system and mild hybrid functions.
Mercedes is rolling out not one, but four brand new engines with eight, six and four cylinders, all equipped with clever tech and modular components across the engines, including a standard 500cc cylinder displacement, help to improve fuel economy and enhance performance.
M176 AMG developed new V8 for the S-Class...
M256 six-cylinder inline gasoline with mild-hybrid tech
Another significant premiere is the new six-cylinder inline gasoline engine (codenamed M256), the first-ever Mercedes engine designed to support mild hybrid and electrification applications right from the outset. It will debut in 2017, again on the flagship S-Class, at first, but it will eventually filter down to the smaller E-Class.
The main innovation is the 48V electrical system. The Integrated Starter-Alternator (ISG) and electric auxiliary compressor (eZV) combine to produce a power boost that negates turbo lag, while the system also serves the classic roles of powering the water pump and air-conditioning compressor. The 48V ISG is also responsible for hybrid functions such as boost (up to 15 kW), energy recovery, coasting and shifting of the load point the engine can be operated in a more favourable area of the engine map; load increase/reduction depending on the state of charge of the battery.
Packaging has a lot gain from the new inline configuration. The engine is shorter due to the absence of a belt drive so Mercedes freed more space for ancillary components on either side of the new inline six cylinder unit. Its performance is also as dynamic as that of a V8, as the new six-cylinder in-line engine comes with an especially intelligent form of turbocharging: assisted by the ISG at start-off, the electric auxiliary compressor (eZV) guarantees immediate high torque when driving off and accelerating, bridging the time before the large exhaust turbocharger cuts in. The electric turbocharger accelerates to 70,000 rpm within 300 milliseconds, ensuring an extremely spontaneous reaction from the engine.
The new engine has 2,999 cc and develops more than 408 hp and 500 Nm (versus 2,996 cc and 333 hp for the old M276 V6) while CO2 emissions have gone down by 15%. Another trick used by Mercedes is the first-ever particulate filter to be mounted on a series gasoline engine. It traps soot particles and it will be gradually appear on all future engines, beyond the all-new M256 inline-six cylinder.
Mercedes-Benz Sechszylinder-Dieselmotor, OM656 // Mercedes-Benz six-cylinder diesel engine, OM656
OM656 six-cylinder inline diesel with 313 hp
The list of brand new engines continues with a 3-liter diesel, again in the inline-six cylinder configuration. Codenamed OM656, Mercedes says this will be the most powerful six-cylinder diesel in its line-up with ample power output of 313 bhp (up from 258 bhp on the old V6).
The new engine features state of the art design. Mercedes says the inline-six cylinder unit uses an aluminium engine block and steel pistons (reducing the friction by 40 to 50 percent), multi-way exhaust gas recirculation and a near-engine exhaust aftertreatment. Also of great importance is the Nanoslide technology an extremely thin, low-friction coating of the cylinder walls, two measures that reduce friction.
Another high-tech solution is the stepped-bowl combustion process named after the shape of the combustion bowl in the piston. The efficiency is increased by the higher burning rate in comparison with the previous omega combustion bowl. The characteristic feature of the specifically configured combination of bowl shape, air movement and injector is its very efficient utilisation of air, which allows operation with very high air surplus. This means that particulate emissions can be reduced to an especially low level.
Fuel consumption has gone down 7%. his is reinforced by the CAMTRONIC switchable exhaust camshaft, which supports the consumption-neutral heating of the exhaust system. The new engine is equipped with multi-way exhaust gas recirculation (EGR). It combines cooled high-pressure and low-pressure EGR. This makes it possible to significantly further reduce the untreated emissions from the engine across the entire engine map, with the centre of combustion being favourable for fuel economy.
M264 four-cylinder petrol with 100 kW per litre...
48V electrical system...
Petrol particulate filter...
Electric auxiliary compressor...
Belt-driven starter-alternator (BSA)...