Mercedes-Benz M278 engine
Encyclopedia
The Mercedes-Benz
M278 engine is a family of direct injected
, V8
gasoline
automotive
piston engines.
The M278 is derived from the company's previous M273
V8 engine, sharing its bore pitch
, aluminum engine block, and Silitec aluminum/silicon low-friction cylinder liners. In contrast to the naturally aspirated M273, however, the M278 features twin turbochargers
, one per cylinder bank, producing up to 0.9 bar
boost pressure. The M278 also features gasoline direct injection
, with piezo-electrically
actuated fuel injectors for more precise fuel delivery, and multi-spark ignition, which enables the spark plugs to be fired multiple times over the combustion sequence for more efficient combustion. Other changes relative to the M273 include an increased adjustment range for the variable valve timing
system, a new timing chain arrangement, and new engine accessories (such as the oil pump, water pump, fuel pump, and alternator) which reduce parasitic loads. Many of these new features are shared with the M276 V6 engine family
, which was announced at the same time.
Mercedes-Benz estimate that these changes, in conjunction with vehicle modifications such as a stop-start system, allow the 4.7 liter M278 to have 22% lower fuel consumption and CO2
emissions than the 5.5 liter M273 while producing more power (429 hp versus 382 hp) and torque (516 ft·lbf versus 391 ft·lbf).
The entire M278 lineup avoids the United States Gas Guzzler Tax
, a first for V8 production engines from Mercedes-Benz.
Applications:
for use in higher-performance models. This version has a displacement of 5.5 liters (5461 cc) with a bore of 98.0 mm and stroke of 90.5 mm. Increased power and torque comes from the increased displacement as well as higher boost pressure of 1.0 bar. Output is 536 hp (400 kW, 544 PS) at 5500 rpm with 590 ft·lbf (800 N·m) of torque at 2000-4500 rpm, or 563 hp (420 kW, 571 PS) at 5500 rpm with 664 ft·lbf (900 N·m) of torque at 2500-3750 rpm with the optional AMG Performance Package. The M157 engine in high-performance E-Class and CLS-Class models will produce 525 hp (386 kW) and 516 ft·lbf (700 N·m) of torque, or 557 hp (410 kW) and 590 ft·lbf (800 N·m) of torque with the AMG Performance Package. These engines are mated to the AMG Speedshift MCT 7-speed dual-clutch transmission.
Applications:
The M157 engine will replace the previous M156 in most of the AMG lineup. Despite the 5.5 liter displacement, all models are designated "63" for marketing purposes.
system for improved fuel economy (up to 30 percent better than the M113 E55 engine used in the previous model). Output is 415 hp at 6800 rpm, with 390 ft·lbf of torque at 4500 rpm.
Applications
Mercedes-Benz
Mercedes-Benz is a German manufacturer of automobiles, buses, coaches, and trucks. Mercedes-Benz is a division of its parent company, Daimler AG...
M278 engine is a family of direct injected
Gasoline direct injection
In internal combustion engines, gasoline direct injection , also known as petrol direct injection or direct petrol injection, is a variant of fuel injection employed in modern two-stroke and four-stroke gasoline engines...
, V8
V8 engine
A V8 engine is a V engine with eight cylinders mounted on the crankcase in two banks of four cylinders, in most cases set at a right angle to each other but sometimes at a narrower angle, with all eight pistons driving a common crankshaft....
gasoline
Gasoline
Gasoline , or petrol , is a toxic, translucent, petroleum-derived liquid that is primarily used as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives. Some gasolines also contain...
automotive
Automobile
An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...
piston engines.
The M278 is derived from the company's previous M273
Mercedes-Benz M273 engine
The Mercedes-Benz M273 engine is a V8 automobile piston engine family used in the 2000s. It was based on the similar M272 V6 introduced in 2004....
V8 engine, sharing its bore pitch
Bore pitch
Bore pitch is the distance between the centerline of a cylinder bore to the centerline of the next cylinder bore adjacent to it in an internal combustion engine...
, aluminum engine block, and Silitec aluminum/silicon low-friction cylinder liners. In contrast to the naturally aspirated M273, however, the M278 features twin turbochargers
Turbocharger
A turbocharger, or turbo , from the Greek "τύρβη" is a centrifugal compressor powered by a turbine that is driven by an engine's exhaust gases. Its benefit lies with the compressor increasing the mass of air entering the engine , thereby resulting in greater performance...
, one per cylinder bank, producing up to 0.9 bar
Bar (unit)
The bar is a unit of pressure equal to 100 kilopascals, and roughly equal to the atmospheric pressure on Earth at sea level. Other units derived from the bar are the megabar , kilobar , decibar , centibar , and millibar...
boost pressure. The M278 also features gasoline direct injection
Gasoline direct injection
In internal combustion engines, gasoline direct injection , also known as petrol direct injection or direct petrol injection, is a variant of fuel injection employed in modern two-stroke and four-stroke gasoline engines...
, with piezo-electrically
Piezoelectricity
Piezoelectricity is the charge which accumulates in certain solid materials in response to applied mechanical stress. The word piezoelectricity means electricity resulting from pressure...
actuated fuel injectors for more precise fuel delivery, and multi-spark ignition, which enables the spark plugs to be fired multiple times over the combustion sequence for more efficient combustion. Other changes relative to the M273 include an increased adjustment range for the variable valve timing
Variable valve timing
In internal combustion engines, variable valve timing , also known as Variable valve actuation , is a generalized term used to describe any mechanism or method that can alter the shape or timing of a valve lift event within an internal combustion engine...
system, a new timing chain arrangement, and new engine accessories (such as the oil pump, water pump, fuel pump, and alternator) which reduce parasitic loads. Many of these new features are shared with the M276 V6 engine family
Mercedes-Benz M276 engine
The Mercedes-Benz M276 engine is a direct injected, V6 gasoline automotive piston engine.The M276 engine is related to the Chrysler Pentastar V6 engine, with which it shares its basic architecture, as it was developed while Chrysler was still owned by Daimler AG. This can be seen in its 60 degree...
, which was announced at the same time.
Mercedes-Benz estimate that these changes, in conjunction with vehicle modifications such as a stop-start system, allow the 4.7 liter M278 to have 22% lower fuel consumption and CO2
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
emissions than the 5.5 liter M273 while producing more power (429 hp versus 382 hp) and torque (516 ft·lbf versus 391 ft·lbf).
The entire M278 lineup avoids the United States Gas Guzzler Tax
Gas Guzzler Tax
The National Energy Act: Energy Tax Act of 1978 , or the Gas Guzzler Tax, imposed set tax penalties on car manufacturers who fail to meet the minimum fuel economy level of in the United States. This does not include minivans, sport utility vehicles or pick-up trucks. It is intended to discourage...
, a first for V8 production engines from Mercedes-Benz.
M278 (base)
The basic M278 has a displacement of 4.7 liters (4663 cc) with a bore of 92.9 mm and stroke of 86 mm. Output is 429 hp (320 kW, 435 PS) at 5250 rpm with 516 ft·lbf (700 N·m) of torque at 1800-3500 rpm for S-Class and CL-Class models, while CLS-Class models are derated to 402 hp (300 kW) with 443 ft·lbf (600 N·m) of torque at 1600 rpm.Applications:
- 2011– Mercedes-Benz S-ClassMercedes-Benz W221The Mercedes-Benz W221 is a chassis code of S-Class, the successor of Mercedes-Benz W220.The vehicle was unveiled in 2005 Frankfurt Motor Show.-Styling:The W221 S-Class' exterior styling is distinctly different to the W220...
- 2011– Mercedes-Benz CL-ClassMercedes-Benz C216The Mercedes-Benz C216 is the new platform for the grand tourer Mercedes-Benz CL-Class. It replaced the C215 platform. The new platform was presented at the 2006 Mondial de l'Automobile. The first right-handed drive model presented at the 28th Bangkok International Motor Show.- Overview :The CL 63...
- 2011– Mercedes-Benz CLS-Class
M157
The second variant, designated M157, is tuned by Mercedes-AMGMercedes-AMG
Mercedes-AMG GmbH, commonly known as AMG, is a subsidiary of the Mercedes-Benz car company specializing in high-performance luxury cars....
for use in higher-performance models. This version has a displacement of 5.5 liters (5461 cc) with a bore of 98.0 mm and stroke of 90.5 mm. Increased power and torque comes from the increased displacement as well as higher boost pressure of 1.0 bar. Output is 536 hp (400 kW, 544 PS) at 5500 rpm with 590 ft·lbf (800 N·m) of torque at 2000-4500 rpm, or 563 hp (420 kW, 571 PS) at 5500 rpm with 664 ft·lbf (900 N·m) of torque at 2500-3750 rpm with the optional AMG Performance Package. The M157 engine in high-performance E-Class and CLS-Class models will produce 525 hp (386 kW) and 516 ft·lbf (700 N·m) of torque, or 557 hp (410 kW) and 590 ft·lbf (800 N·m) of torque with the AMG Performance Package. These engines are mated to the AMG Speedshift MCT 7-speed dual-clutch transmission.
Applications:
- 2011– Mercedes-Benz S63 AMGMercedes-Benz W221The Mercedes-Benz W221 is a chassis code of S-Class, the successor of Mercedes-Benz W220.The vehicle was unveiled in 2005 Frankfurt Motor Show.-Styling:The W221 S-Class' exterior styling is distinctly different to the W220...
- 2011– Mercedes-Benz CL63 AMGMercedes-Benz C216The Mercedes-Benz C216 is the new platform for the grand tourer Mercedes-Benz CL-Class. It replaced the C215 platform. The new platform was presented at the 2006 Mondial de l'Automobile. The first right-handed drive model presented at the 28th Bangkok International Motor Show.- Overview :The CL 63...
- 2012– Mercedes-Benz CLS63 AMG
- 2012– Mercedes-Benz E63 AMGMercedes-Benz W212The Mercedes-Benz W212 is a sedan sold as the ninth-generation E-Class, replacing the previous W211 model. C207 is the chassis code for the related E-Class Coupe, a replacement for the CLK-class coupe and cabriolet...
The M157 engine will replace the previous M156 in most of the AMG lineup. Despite the 5.5 liter displacement, all models are designated "63" for marketing purposes.
M152
The third variant, designated M152, is a naturally aspirated derivative of the M157 engine, sharing the same displacement, direct injection, and many other features. The M152 engine includes a variable displacementVariable displacement
Variable displacement is an automobile engine technology that allows the engine displacement to change, usually by deactivating cylinders, for improved fuel economy. The technology is primarily used in large, multi-cylinder engines...
system for improved fuel economy (up to 30 percent better than the M113 E55 engine used in the previous model). Output is 415 hp at 6800 rpm, with 390 ft·lbf of torque at 4500 rpm.
Applications
- 2012– Mercedes-Benz SLK55 AMGMercedes-Benz R172The R172 represents the third generation of Mercedes-Benz SLK, and was launched in January 2011 with international sales starting spring 2011. Replacing the R171, the R172 continues the small luxury roadster concept that was initiated by the first SLK launched in 1996...