An entire family of high-performance AMG models are powered by the first engine developed entirely by AMG. The naturally aspirated 6.3-liter V8 produces between 451 and 518 horsepower, depending on the model.
The V8-powered AMG model lineup featuring this engine includes the C63 AMG, E63 AMG and S63 AMG sedans; the CL63 AMG and CLS63 AMG coupes; the ML63 AMG sport utility vehicle and the SL63 AMG roadster.
AMG Racing Success Spawns High-Power Production Engine
One of the most powerful naturally aspirated production V8s ever, the M156 engine boasts a wealth of exciting features derived from AMG’s highly successful racing efforts.
Built almost completely from a high-strength silicon-aluminum alloy, the 6.3-liter features four valves per cylinder, variable valve timing, bucket followers (rather than rocker arms) and a variable-length intake manifold.
Crankcase Bedplate Instead of Main Bearing Caps
For greater strength and reliability, the AMG engine uses a rigid one-piece bedplate at the bottom of the engine block instead of individual main bearing caps that can distort or loosen at high RPM.
With cast-in steel inserts for greater strength, the aluminum bedplate essentially sandwiches the crankshaft between two sections of the sturdy engine block.
A Racing Crankshaft
Made of high-quality 42CrMo4V forged steel alloy, a finely balanced crankshaft with six counterweights spins in five main crankshaft bearings.
The crankshaft counterweights feature heavy metal plugs – a detail usually found only in racing engines – which means the counter-weights can be much smaller, increasing power by reducing rotational inertia and oil drag.
Each forged connecting rod is precisely “cracked” with the help of a laser beam, so the irregular fracture contributes to its strength when the two halves are clamped around the crankshaft.
The connecting rods and lightweight pistons are matched for extremely close weight tolerances that contribute to smooth running at high speeds. Small nozzles in the engine block spray cooling oil onto the underside of each piston crown.
TWAS Twin-Wire-Arc-Sprayed Cylinder Bores
The cylinder bores feature a twin-wire-arc-sprayed (TWAS) coating, an innovative process that results in impressively low friction and running surfaces that are twice as hard as conventional cast-iron cylinders.
The engine block and cylinder heads are made of cast aluminum silicon alloys (AlSi7 and AlSi17), which represent the state of the art in terms of strength, light weight and thermal benefits.
First, a high-pressure water jet roughens the cylinder bores. Then two electrode wires and an atomizing gas form plasma under high voltage.
In essence, the atomizing gas sprays molten metal from the wires onto the cylinder walls, where it solidifies, forming an extremely hard coating.
A honing process finishes the cylinder bores, exposing micro-pores in the hard coating that will retain oil and ensure good lubrication of the pistons and piston rings.
Vertical Intake and Exhaust Ports
Adapted from racing designs, air passing through the engine follows a straight line down through the intake manifold into its hemispherical combustion chambers and out the exhaust passages.
A patented dual-length intake manifold is part of the vertical intake and exhaust system. The engine shares no parts with Mercedes-Benz V8 engines.
Operated by the Bosch 9.7 engine management system, two electrically-operated internal flaps control air flow through a variable-length magnesium manifold.
At relatively low engine speeds, intake air flows through long runners, which helps to maximize engine torque. At higher engine speeds, the flaps allow intake air to flow through shorter pipes for maximum high-speed horsepower.
Two integral hot film air mass sensors behind the air cleaners provide the engine electronics with information about the density and temperature of the incoming air.
“Bucket” Followers Instead of Rocker Arms
The AMG-designed engine also features a sophisticated valve train, also adapted from the AMG racing engines. Each intake valve is 40 millimeters in diameter, while exhaust valves measure 34 mm.
Twin overhead camshafts in each cylinder bank open the 32 valves via bucket-type followers. In other words, instead of rocker arms, the cam lobes sweep across the flat tops of the buckets, which sit directly on top of the valve stems.
This space-saving design provides a very stiff valve train that allows for large valve openings and dependable high-speed operation for maximum horsepower and torque.
However, in contrast to racing engines, each bucket incorporates a hydraulic lifter that automatically maintains valve clearance, which allows for long service intervals and low costs.
Variable Valve Timing
The AMG V8 makes use of variable intake and exhaust valve timing to maximize efficiency and torque over a wide RPM range.
Valve timing can be automatically adjusted within a range of 40 degrees using electro-hydraulic vane-type adjusters on each camshaft.
At part throttle, the valve timing adjuster keeps the exhaust valves open as the intake valves are opening, using this valve overlap to create internal exhaust gas recirculation, reducing exhaust emissions and improving fuel economy.
However, approaching full throttle, the camshaft adjustment optimizes valve timing for maximum power. The intake cams are driven by a double chain from the crankshaft, and small gears on the intake cams drive the exhaust camshafts.
AMG’s Supercharged V8
Based on earlier engine architecture, a supercharged V8 powers the G55 AMG – with a dual side pipe exhaust system that produces 500 horsepower.
A normally aspirated 355-hp version of this 5,439-cc V8 is used in the SLK55 AMG model. For these models, the AMG V8 engine makes easy work of the 0-60 mph test track sprint in 4.9 seconds for the SLK and 5.4 seconds for the G55 AMG.
A Powerful Kompressor Between Cylinder Banks
The AMG Kompressor V8 in the G55 AMG makes impressive power, due in large part to a belt-driven “Lysholm” or screw-type supercharger that develops about 30 percent more intake pressure than other comparable supercharging systems.
Each Teflon-coated rotor spins at a maximum of over 23,000 rpm and, in doing so, can push up to 4,000 pounds of air per hour into the engine’s combustion chambers (at 70 degrees F, sea level).
The maximum boost pressure is 0.8 bar or 11.6 pounds per square inch.
The engine management unit determines whether to engage the supercharger depending on the engine speed and load. Under light loads, when the throttle is open only slightly, the Kompressor V8s operate purely as a naturally aspirated engine.
However, the supercharger goes into instant action when the driver accelerates. Under 2,700 rpm, the supercharger runs only when the throttle is open and the engine is under load, but above 2,700 rpm, the supercharger is engaged full-time.
This nets many advantages – thermal efficiency, fuel consumption, noise and exhaust emissions.
The load- and rpm-dependent operation is carried out by an electromagnetic clutch that gets its signals directly from the fully electronic Bosch ME 2.8.1 engine management system.
The driver doesn’t feel or hear the supercharger activation. Torque build-up is extremely smooth, and the supercharged V8 engine shows its muscle evenly throughout the rpm range.
Compact Water-Cooled Intercooler
To improve efficiency even further, an intercooler sits between the cylinder banks, operating as an air-to-water heat exchanger, extracting heat from the compressed air and transferring it to the coolant.
A dedicated pump allows the water to flow through a special low-temperature cooler located between the air conditioning condenser and the radiator, and this system works independently of the primary coolant circuit for the engine.
In contrast with air-to-air systems – in which ignition timing and engine power must be reduced under high thermal load – this advanced water-to-air cooler enables the full output and torque of the supercharged V8s to be on tap at all times.
Also, an oil cooler is housed in the front apron.
The Sound of Power
Both types of V8 engines come with an exhaust system that’s just as sophisticated as the rest of the car. With the exception of the two exhaust manifolds, the complete exhaust systems of each Mercedes-AMG model have been designed specifically for that application.
All four catalytic converters feature thin-wall ceramic material, and large surface area inside the ceramic element ensures low exhaust back pressure, benefiting both performance and exhaust emissions.
The resulting sound emanating from the twin-oval AMG tailpipes is also distinctively throaty.
One Man, One Engine – Individual Hand Craftsmanship
Each new AMG engine is hand-assembled one at a time by an expert craftsman at Mercedes-AMG in Affalterbach, Germany.
Mercedes-AMG follows a philosophy of “one man, one engine,” which means that a single technician – identified by the signature plate affixed to the engine – is responsible for the complete assembly of an AMG high-performance engine from start to finish.
With the utmost care, the craftsman installs each and every part – from the crankshaft, connecting rods and pistons to the intake system, wiring harness and oil fill-up. Each new engine is bench-tested to ensure consistent quality and maximum performance.
AMG has been the high-performance subsidiary of Daimler AG since 1999 and is located near Stuttgart in the country village of Affalterbach, Germany. AMG employs more than 600 specialists in development, production and administrative areas.
AMG develops each of its models, including the transmission, chassis, brakes, aerodynamics, interior and – most importantly – the engine.
AMG engines are the product of a surprising combination of cutting-edge technology, computer-aided design and old-fashioned hand craftsmanship.
No automobile capable of eye-popping flat-out performance also displays such a docile nature in every-day driving. Each engine is produced and tested at AMG’s headquarters in Affalterbach, and AMG models are assembled at the main Mercedes-Benz vehicle manufacturing plants.
With more than 50 percent of AMG sales, the U.S. is the top market for AMG worldwide.
While all Mercedes-Benz authorized dealers offer AMG products, about 25 U.S. dealerships serve as AMG Performance Centers, which include specially trained staff, uniquely branded point-of-sale materials and highly popular “AMG Performance Tour” weekend driving events.
AMG also offers track-based Driving Academy and AMG Challenge programs.
The new AMG V8 power unit with 375 kW/510 hp
The world’s most powerful naturally aspirated eight-cylinder engine – made by Mercedes-AMG
Le Castellet – Mercedes-AMG has taken a completely new departure: the new AMG 6.3-litre V8 engine is the first in the world to combine the high-revving concept with a large displacement.
Developed entirely by AMG, this high-performance engine has a displacement of 6.3 litres and generates an output of 375 kW/510 hp at 6800 rpm, plus a maximum torque of 630 Newton metres, which makes the new power pack by AMG the world’s most powerful naturally aspirated eight-cylinder production engine.
Thanks to its large displacement, the V8 by AMG develops around 20 percent more torque than comparable naturally aspirated engines in this performance class.
Made completely from high-strength aluminium, this naturally aspirated V8 engine has a wealth of exciting features derived from motorsport, and impressively documents the successful motor racing history of AMG.
Together with a variable intake manifold featuring two integral throttle flaps, the vertical arrangement of the intake and exhaust ducts ensures perfect cylinder charging.
Bucket tappets in the cylinder heads allow a stiff valve train and therefore high engine speeds.
Variable camshaft adjustment, a particularly rigid closed-deck crankcase and cylinder walls with a new, revolutionary LDS coating are further attributes of this ultra-modern
V8 engine made by Mercedes-AMG.
This eight-cylinder unit was developed to series production maturity entirely by the efforts of the engineers and technicians in Affalterbach.
The new AMG 6.3-litre V8 engine will shortly be presented in a new high-performance AMG car, and is destined to provide both emotional and physical driving pleasure in other AMG cars in the future.
The high expectations of AMG customers and the impressive history of AMG eight-cylinder engines were both an incentive and an obligation for the engineers and product planners at Mercedes-AMG GmbH to come up with a superlative new V8 power unit.
A mere glance at the key technical data shows that this has been achieved: from a displacement of 6208 cubic centimetres, the AMG V8 aluminium engine develops a peak output 375 kW/510 hp at 6800 rpm and a maximum torque of 630 Newton metres which is available from 5200 rpm. The maximum engine speed is 7200 rpm.
Keys figures at a glance:
|Compression ratio |
|11.3 : 1|
|Output||375 kW/510 hp |
at 6800 rpm
|Max. torque||630 Nm at |
This unique combination of a fast-running concept and a large displacement achieves the best of both worlds: exhilarating flexibility accompanied by high torque at low engine speeds.
The driver experiences the decidedly sporty character of the engine in the form of great agility and dynamic responsiveness in all engine speed ranges.
The new AMG V8 already delivers 500 Newton metres to the crankshaft at 2000 rpm, while the maximum of 630 Newton metres is on tap at 5200 rpm – more than any other naturally aspirated engine in this output and displacement class.
In short, the new AMG eight-cylinder guarantees dynamic acceleration, rapid intermediate sprints and sheer driving pleasure at the highest level.
With its new, sporty AMG exhaust note which was designed during an extensive series of tests, the eight-cylinder unit from Affalterbach offers the excitement of a naturally-aspirated, fast-running V8 engine in unmistakable audible and palpable form at low, medium and high engine speeds.
Unique variable intake manifold and revolutionary cylinder walls
Apart from the large overall displacement, the extremely high output and torque is above all due to the sophisticated intake system – a completely new departure for AMG.
Its major characteristics are large cross-sections, the streamlined design of the entire intake and exhaust manifolds, and the vertical arrangement of all ducts in line with motor-racing practice.
The newly developed and patented variable intake manifold, which is made of magnesium and has two parallel-action internal throttle flaps, is a world first.
The combined action of these components, which are highly unusual in regular engine production, ensures perfect cylinder charging.
The 32 valves in the cylinder heads are operated by bucket tappets for a rigid valve train and high engine speeds – a technology which has proved its worth in motor racing.
Continuous adjustment of the camshafts on the intake and exhaust sides is another special feature of this up-to-date AMG V8 engine.
The interior of this powerful new development conceals yet another genuine world first, too: as the world’s first regular production engine, the AMG 6.3-litre V8 engine features a special twin-wire-arc-sprayed (TWAS) coating on the cylinder walls, a new process which produces outstandingly low friction.
Motor racing genes are once again obvious in the crankcase: as in the supercharged AMG V8 engine for the Mercedes-Benz SLR McLaren, the engineers and technicians opted for a particularly rigid bedplate design with closed-deck technology.
Special, cast-in steel components ensure even more rigidity, a reliable oil supply in all everyday operating situations and optimal long-term durability.
Completely autonomous development from Affalterbach
In design terms the new eight-cylinder engine by Mercedes-AMG is the first completely autonomous development to have no features or shared parts whatsoever in common with other eight-cylinder units by Mercedes-Benz.
The new 6.3-litre unit differs from the other AMG V8 engines based on Mercedes designs in the distance between cylinders, the crankcase concept, the sophisticated intake and exhaust manifolds and the valve train; the bore/stroke ratio is also a completely new departure for Mercedes-AMG.
The new powerpack is produced at the ultra-modern AMG engine workshops, according to the “one man, one engine” philosophy. This means that a single technician assembles the complete engine by hand – as witness his signature on the engine’s AMG badge.
Successful history of high-performance AMG engines
AMG engines have always been in a class of their own. The first highlight was the 6.8-litre, 309-kW/420-hp V8 racing engine in the legendary 300 SEL 6.8 AMG of 1971.
At the 24-hour race in Spa-Francorchamps this fast Mercedes saloon immediately secured a highly acclaimed class victory and second place overall.
Other milestones in the history of AMG included the first four-valve V8 of 1984, which generated 250 kW/340 hp from a displacement of five litres, and the 6.0-litre eight-cylinder engine with 283 kW/385 hp.
The 368-kW/500 –hp, 5.5-litre supercharged V8 engine in the SL 55 AMG, the supercharged AMG
V8 engine generating 460 kW/626 hp in the Mercedes-Benz SLR McLaren and the AMG V12 biturbo engine with an output of 450 kW/612 hp and 1000 Newton metres of torque are further highlights in the history of AMG engine technology.
In 2003 and 2004, both the AMG 5.5-litre supercharged V8 and the AMG 6.0-litre V12 biturbo engine took first place against well-known competitors in the “Best Performance Engines” category of the “Engine of the Year Awards”.
Development aims and philosophy:
Synthesis of outstanding performance and everyday practicality
- The world’s most powerful naturally aspirated V8 production engine with 375 kW/510 hp
- Effortless torque of 630 Newton metres
- Great agility, outstanding liveliness and enormous tractive power
- Smooth running for typical Mercedes long-distance comfort
- Newly developed entirely by Mercedes-AMG GmbH
Outstanding performance and a wide usable engine speed range, a good power-to-weight ratio and sound design, a low specific fuel consumption and exhaust emission values, ease of maintenance and pedestrian protection – the requirements for newly developed engines are both varied and demanding.
The same applied to the completely new AMG 6.3-litre V8 engine. The primary development goals for the engineers and product strategists at Mercedes-AMG GmbH were dynamic responsiveness, great agility, exhilarating liveliness and a high torque even at low engine speeds.
Key figures at a glance:
|Cylinder arrangement |
|Cylinder angle |
|Valves per cylinder |
|Dist. between cylinders |
|Compression ratio |
|11.3 : 1|
|Output||375 kW/510 hp |
at 6800 rpm
|Output per litre||60.4 kW/82.1 hp|
|Max. torque||630 Nm at |
|Torque per litre||101.5 Nm|
|Maximum engine speed |
|Power-to-weight ratio |
A glance at the key technical data shows that the aim of developing a naturally aspirated, fast-running V8 engine with a decidedly sporty character was achieved in full: the new AMG engine generates a maximum output of 375 kW/510 hp at 6800 rpm from a displacement of 6208 cubic centimetres.
The new powerpack also reaches new heights where maximum torque is concerned: 630 Newton metres are on tap at 5200 rpm.
This makes it the world’s most powerful naturally aspirated eight-cylinder engine, as no other unit in this output and displacement class is able to achieve these figures.
A look at the torque curve also reveals its extraordinary characteristics: the new AMG V8 already delivers 500 Newton metres to the crankshaft at 2000 rpm, increasing to no less than 560 Newton metres at 3000 rpm – considerably more than the maximum values comparable engines are able to achieve at much higher engine speeds.
These remarkable figures reflect the Mercedes-AMG philosophy of building powerful engines with superlative output and torque characteristics, combined with dynamic and immediate responsiveness, which will enable drivers to use a sporty style of driving to the full.
With its unique, sporty AMG sound which was designed during an extensive series of tests, the eight-cylinder unit from Affalterbach offers the excitement of a naturally-aspirated, fast-running V8 engine in unmistakable audible and palpable form at low, medium and high engine speeds.
Despite its pronounced sportiness, its smooth running characteristics and wide usable torque range also allow more leisurely progress when preferred – guaranteeing the long-distance comfort which is so typical of a Mercedes.
Completely autonomous development from Affalterbach
In conceptual and design terms the new eight-cylinder powerplant by Mercedes-AMG is a completely autonomous development which shares no features or common parts with other eight-cylinder engines by Mercedes-Benz.
The new 6.3-litre unit differs from the other AMG V8 engines based on Mercedes designs in the distance between cylinders, the completely new crankcase concept, the sophisticated intake and exhaust manifolds and the valve train.
The bore/stroke ratio is also a completely new departure for Mercedes-AMG.
Focusing on outstanding output and torque characteristics and decidedly sporty performance requires sophisticated technologies and solutions which are often based on motor sports engineering – which means that for mile after mile, the AMG driver benefits from more than 35 years of experience in international motor racing.
Design and materials:
Know-how from motor sports
- Particularly rigid bedplate crankcase of closed-deck design
- Cylinder walls with a unique, revolutionary TWAS coating
- Completely new dual-length intake manifold with integral throttle flaps
- Vertical air ducts, valve control by bucket tappets
- Completely autonomous development from Affalterbach
More than three decades of know-how gained in GT and Touring Car championships, as well as great experience in the production of powerful, high-performance engines, went into the design of the new AMG 6.3-litre eight-cylinder engine.
The special production facilities at the Affalterbach location were already taken into consideration during the development and conceptual phases, which allowed freedom of action and new possibilities for the engine’s designers.
The resulting masterpiece was only made possible by a unique combination of extremely advanced engine and materials technology.
Sophisticated air ducting for a high output
Apart from the large overall displacement of precisely 6208 cc, the extremely high output and torque is above all due to the sophisticated intake system – a completely new departure for AMG.
Together with the innovative, variable intake manifold of magnesium with two integral throttle flaps, the large air intake cross-sections familiar from motorsport, the streamlined design of the intake and exhaust ducting and the vertical arrangement of the intake and exhaust ducts ensure that all eight cylinders are perfectly charged.
Patented variable intake manifold with two internal throttle flaps
The patented, dual-length intake manifold with two internal throttle flaps is a world first. Its task is to ensure a strong torque curve by lengthening the airflow distance at low engine speeds.
At higher engine speeds the intake manifold switches to short airflow distances to achieve a high peak performance.
The switching process is monitored by the electronic engine management system, vacuum-controlled depending on the engine load and engine speed, and imperceptible to the vehicle’s occupants.
The interior of the light, die-cast magnesium intake manifold features two electronically operated throttle flaps which are adjustable within fractions of a second: they can be opened to their maximum in just 100 milliseconds, and the driver perceives this as extraordinary responsiveness.
The air intake at the front of the vehicle is of dual-flow design; two integral hot film airflow sensors behind the air filters provide the engine electronics with the necessary information about the temperature and density of the intake air.
With the help of complex flow simulations the engineers at Mercedes-AMG have precisely configured all the intake ducting to meet the requirements of the large engine displacement and the resulting large air volumes.
Valve operation by bucket tappets, as in the racing engines
Another special feature of the new AMG V8 engine is the sophisticated valve train, which is also derived from the powerful AMG racing engines. The 32 valves in the cylinder heads are operated by bucket tappets.
Their space-saving design allows a stiff valve train and therefore high engine speeds with large valve opening cross-sections, which in turn benefits output and torque.
The large intake valves have a diameter of 40 millimetres, while their opposite numbers on the exhaust side measure 34 millimetres.
In contrast to a racing engine, the valve clearances are automatically adjusted by a hydraulic mechanism – the customer benefits from long, variable service intervals and low costs.
Four continuously variable overhead camshafts
All four overhead camshafts are continuously variable over a range of 42 degrees. Both the intake and exhaust camshafts are adjusted as a function of engine load and engine speed, ensuring extremely high output and torque values and smooth idling, and especially low exhaust emissions.
Depending on the engine speed, the valve overlap can be varied to ensure an optimal supply of fuel/air mixture to the combustion chambers and efficient venting of the exhaust gases.
This variable camshaft adjustment is controlled electro-hydraulically and monitored by the engine management system; the system is driven by a duplex roller chain and intermeshing pairs of gear wheels.
Crankcase with bedplate and closed-deck design
When designing the crankcase, the engineers and technicians in Affalterbach opted for a sophisticated bedplate construction on the closed-deck principle, which is well established in the motor racing sector and is also used in the powerful, supercharged AMG 5.5-litre V8 engine of the Mercedes-Benz SLR McLaren.
Amongst engine specialists, this configuration stands for a high-performance sporting engine which is uncompromisingly designed for the utmost robustness.
The lower section of the crankcase in the AMG 6.3-litre V8 engine is an enclosed unit, which particularly benefits the torsional rigidity of the engine.
This type of construction also permits higher combustion pressures and reduces pulsation losses within the crankcase itself. This not only minimises the internal friction losses, but also produces more rigid bearing bridges for the crankshaft.
More efficient integration of the oil scavenger also allows foaming on the part of the engine oil to be reduced. The crankcase is also equipped with special, cast-in steel components which improve the strength of the engine block even further, benefit the engine acoustics and ensure a reliable oil supply.
Unique process for cylinder wall coating
The engine block and cylinder heads are of cast aluminium-silicon alloys (AlSi7 and AlSi17) which represent the state of the art in terms of weight, thermal and mechanical resistance and long-term strength.
The engine specialists at Mercedes-AMG use a particularly advanced process for the eight cylinder walls to produce a tribologically optimal surface, namely a coating applied by twin wire arc spraying (TWAS). The advantages of this technology are extremely low friction and wear accompanied by outstanding long-term durability.
A considerably harder surface is achieved compared to conventionally coated cylinder walls. In fact the cylinder walls of the new AMG V8 engine are twice as hard as conventional cast iron liners – a quantum leap for engine specialists.
No other series-production engine apart from the new AMG 6.3-litre V8 unit can boast such sophisticated technology – which means that once again, Mercedes-AMG has underlined its pioneering role in the development and production of innovative high-performance engines.
During the TWAS process, two metallic wires and an atomising gas are brought together in a coating unit. Passing a high voltage through the tips of the wires breaks the gas molecules down to form a plasma, and the wire tips begin to melt.
The atomising gas removes molten metal from the wire tips and sprays these particles onto the cylinder walls to be coated, where they solidify. This is preceded by a high-pressure water jet which roughens the cylinder walls so that the individual sprayed particles adhere to the surface during the TWAS coating process.
The cylinder walls are then honed to achieve a perfect surface structure. During this process the micro-pores in the sprayed coating are partially exposed, which enables them to retain oil when the engine is running and ensure tribologically favourable lubrication of the pistons and piston rings.
This trailblazing process was developed in close collaboration between the DaimlerChrysler process engineering department and Mercedes-AMG, and has been brought to series production maturity for the first time in the AMG V8 engine.
Crank assembly optimised for the lowest possible inertia
The finely balanced crankshaft is designed for the highest stresses, consists of the high-quality forged steel alloy 42CRMo4V, rotates in five crankshaft bearings and features six counterweights for perfectly balanced masses.
Torsional rigidity, long-term structural strength and inertia characteristics are also to the very highest standards. As a detail normally only found in racing engines, the counterweights feature heavy metal core plugs, which means that they can be made significantly more compact.
As a result the complete crank assembly can be optimised for particularly low rotational and oscillatory inertia, which enormously benefits responsiveness and flexibility.
Two lightweight connecting rods forged by the cracking process are connected to each of the four crank pins. During this process, the utmost production precision is made possible by a predetermined breaking point created by a laser beam.
Extremely close weight tolerances between the eight connecting rods are also ensured by precision machining. The same principle is also used for the cast, lightweight pistons.
They are made from a durable high-temperature alloy. Pressure-controlled oil spray nozzles in the crankcase ensure optimal cooling of the highly stressed piston crowns.
Owing to the large overall displacement, a highly efficient oil pump with a high throughput is used in the new AMG eight-cylinder.
Even at high rates of lateral acceleration, the intelligent arrangement of all the components in the oil circuit ensures a consistent supply of lubricant.
The engine oil is cooled on a vehicle-specific basis, i.e. the sump and the arrangement of the coolers may vary. The cooling performance itself always remains constant.
Engine cooling on the sophisticated cross-flow principle
As in thoroughbred racing engines, the engine is cooled on the sophisticated cross-flow principle. This means that the eight individual cylinders have a uniform temperature by virtue of the homogenous coolant flow, thereby avoiding critical temperature peaks.
The coolant flows from the exhaust side of the crankcase across the cylinder heads, then back to the thermostat and radiator via the collector on the intake side.
The thermally highly stressed cylinder heads are also cooled according to this principle, which particularly benefits the operating life.
Even the cylinder head bolts are included in the coolant circuit. This technology was developed with the help of complex flow calculations and perfected during an extended series of tests.
Variable coolant control for optimised friction
In addition the temperature of the coolant is variably controlled. In the interests of optimal in-engine friction and fuel economy, the temperature of the coolant can for example be lowered to 80 degrees Celsius under partial load.
Under full load conditions the temperature is raised to 100 degrees within milliseconds to achieve the best possible engine cooling. The thermostat controlling the coolant temperature receives its instructions from the engine electronics.
Fuel supply monitored by a computer
The fuel supply of the AMG eight-cylinder is likewise computer-controlled and monitored. The fuel pressure is variably and instantly adjusted depending on the performance requirement and ambient temperature.
The engine electronics execute commands from the accelerator pedal within milliseconds, leading to outstanding responsiveness. A high-pressure pump configured for the engine is integrated into the fuel tank.
Highly efficient engine electronics for every function
All engine functions are controlled and executed by a particularly efficient Bosch ME 9.7 control unit. Fuel injection, ignition, the variable intake manifold, camshaft adjustment and variable cooling are all controlled by the state-of-the-art engine computer, which also communicates with all the other onboard control units.
The microprocessor has 10,000 different characteristic maps and functions in its memory, and is able to carry out up to 70 million individual operations per second.
To reduce the load on the engine control unit, the eight individual ignition coils have an integral electronic module known as an ignition amplifier at each cylinder. These ensure a strong ignition spark at all engine speeds and under all load conditions.
Exhaust technology and sound design:
Low emissions and a designer sound
- Continuous camshaft adjustment for low untreated emissions
- Four ceramic catalytic converters of thin-wall substrate design for efficient emissions control
- Characteristic engine sound as a result of extensive tests
- AMG sports exhaust system with two twin tailpipes
Despite its high output and torque values, the new AMG 6.3-litre eight-cylinder engine meets all current exhaust emission standards without difficulty.
Both the European EU-4 standard and the stringent US standards presently in force and planned are complied with. The new AMG engine easily meets specific requirements for the US market, e.g. Onboard Diagnosis II and oxygen sensor diagnosis.
This is due to highly sophisticated engine and exhaust technology. Continuous camshaft adjustment makes a major contribution to efficient emissions control.
Under partial load it ensures need-related internal exhaust gas recirculation by conducting the gases directly from the combustion chamber to the intake ducts.
While the intake valves are being opened the exhaust valves also remain open for a short time, and at this point some of the exhaust gases flow from the exhaust to the intake side.
The engineers at AMG have used this principle of valve overlap to achieve a dual advantage, for both untreated emissions and fuel consumption can be lowered by reducing gas cycle losses.
An exhaust system specially developed for the large-displacement AMG V8 engine is used to support the in-engine emissions control measures.
Effective aftertreatment begins in the air-gap-insulated manifolds, which have a wall thickness of only 1.0 milimetres.
Tens seconds after starting, these already allow an exhaust temperature of 280 degrees Celsius – a precondition for rapid response by the close-coupled catalytic converters.
All four ceramic catalytic converters feature thin-wall substrates; thanks to their maximised surface area
these not only provide the best conditions for effective emissions control, but also aid performance with their low exhaust counterpressure.
Four oxygen sensors are used to control and monitor the exhaust system: the two front sensors ensure an optimal controlled engine range, while the two sensors behind the catalytic converters are responsible for Onboard Diagnosis II.
Secondary air injection reduces carbon monoxide and hydrocarbons
The afterburning effect of the secondary air injection system leads to higher exhaust gas temperatures and supports the heating-up process. As a result of this complex system the carbon monoxide and hydrocarbon content in the exhaust gases is reduced.
The oxygen sensors continuously monitor the constituents of the mixture and supply this information to the computer, which readjusts the mixture as soon as the temperature of the catalytic converters has reached its nominal level.
The new AMG engine also has a demand-related oxygen control system. This means that in all operating conditions, the constituents of the intake mixture can be precisely controlled to avoid damaging the catalytic converters.
This also benefits the fuel consumption under full load, as the mixture can be leaner than in engines without this intelligent control system.
Designer engine sound adds to the power experience
Customers expect a new AMG high-performance engine to possess a characteristic and throaty sound. The primary aim of the technicians was also to create a synthesis of palpable dynamism and the long-distance comfort typical of a Mercedes.
During acceleration the driver experiences the emotional sound of the fast-running engine and the exceptional power of the naturally aspirated eight-cylinder.
At the same time this powerpack must for instance exhibit the smooth running characteristics and effortless progress required when covering long motorway distances.
During this work the specialists at AMG were at pains to avoid disturbing noises and emphasise the pleasant frequencies which are typical of a sports car.
At the same time it was important to comply with all the relevant regulations – for example when measuring drive-by noise.
These varying requirements were a major challenge for the engineers and technicians at Mercedes-AMG GmbH, and they passed the test with flying colours – the results are well worth hearing.
Research in the acoustics laboratory and during test drives
Complex test series both in the acoustics laboratory and during vehicle trials led to a completely newly designed, twin-pipe exhaust system with pipe cross-sections and silencer volumes precisely suited to the engine displacement.
Depending on the vehicle model, not only the routing of the pipes and the position and size of the rear silencers, but also the location of the catalytic converters and oxygen sensors had to be defined.
The two oval, chrome twin tailpipes of the AMG sports exhaust system are not only a striking visual characteristic – the dynamic AMG V8 exhaust note instantly tells the knowledgeable person that this is a genuine AMG.
Close attention was also paid to the intake noise. The aim was to create a sporty but in no way irritating sound for the AMG eight-cylinder. To this end various components were used during the development phase.
When designing the dual-flow intake system, numerous variations of intake ducts, air filters and intake noise dampers were experimented with before the final result was achieved.
Trials and test bench technology:
Endurance trials as a development standard
- Systematic development work in two parallel programmes
- The latest high-tech test benches for engines with up to 735 kW/1000 hp
- Extended trials in all the world’s climatic zones
- Maximum stress in the most extreme endurance trials
Trials of the new AMG 6.3-litre eight-cylinder engine were conducted in two stages. In addition to in-vehicle trials on every continent, the engine had to prove its worth on the newly constructed high-tech test benches in Affalterbach.
But the development work started with analyses of basic mechanical functions, the oil circuit, power characteristics with various intake duct and camshaft configurations, plus the definition of fuel injection quantities, fuel consumption and exhaust emission values – all these were studied on the dynamic simulation test benches at Mercedes-AMG.
Nine of the very latest, high-tech test benches are available in the completely new Mercedes-AMG test bench laboratory, which was taken into commission in 2004; engines with outputs exceeding 735 kW/1000 hp can be dynamically tested in this facility.
After completion of the basic work in Affalterbach, the first test vehicles equipped with the new AMG eight-cylinder engine were sent onto public roads and test tracks in all the climatic regions of the earth.
All of them were required to undergo the standardised trials to which all AMG high-performance cars are subjected.
These place the most extreme demands on the vehicles and their components in terms of practicality, reliability and long-term durability – after all, the new engine must operate perfectly anywhere in the world, and under all climatic and road conditions.
The individual trial stages at a glance:
Engine and transmission development
- High-altitude trials in Denver, Colorado (USA), Lesotho (South Africa) and Granada (Spain)
- Heat trials in Death Valley, California (USA), Upington (South Africa), Idiada test track (Spain) and Phoenix, Arizona (USA)
- Road trials in Los Angeles, California (USA)
- Cold trials in Arctic Falls (Sweden
Cooling and fuel system
- Various test runs on the high-speed circuits in Nardo (Italy) and Papenburg (Germany)
- Trials in Upington (South Africa) and Death Valley, California (USA)
- Tests in the DaimlerChrysler wind tunnel
In addition, various endurance trials were carried out with the aim of simulating the engine’s entire operating life under the most extreme conditions:
- Nürburgring north loop: The engine was tested under predominantly full load conditions on the world’s most demanding racetrack.
- Mixed road endurance trials: Testing under everyday conditions. The vehicles were loaded up to their gross vehicle weight and subjected to a precisely defined test programme on country roads, motorways and in city traffic.
- Stress endurance trials at the DaimlerChrysler test site in Papenburg: Extreme acceleration and deceleration cycles under predominantly full load conditions, with high stresses on the oil circuit, cooling system and fuel supply.
- Endurance trials in the hills of the Swabian Alb region: The vehicles were loaded up to their gross vehicle weight and towed a two-tonne trailer. The route covered country roads with numerous uphill and downhill gradients, and subjected the engine, transmission and cooling system to very high stresses.
In parallel with the road and racetrack trials in various test vehicles, the new AMG 6.3-litre V8 engine was subjected to rigorous tests on the ultra-modern dynamic test benches at AMG.
These facilities are able to simulate any road and environmental conditions to represent any conceivable type of operation. Cold or hot starting, mountain passes, stop-and-go traffic or fast laps on the Grand Prix circuit in Hockenheim – the engines were required to give their utmost.
Even the intake air temperatures and densities can be varied by computer control, and the engines can be alternately filled with hot and cold coolant. Fuels of different grades are also available.
The aim of these extended test bench trials, which also included various endurance tests of up too 800 hours, was to confirm the performance of all the engine components and the peripheral units.
All the stored measuring results for the tested engines were systematically compared and evaluated with the help of reproducible test procedures.
“One man, one engine” in Affalterbach
- AMG engine workshops with an effective floorspace of 9950 sq. m.
- Only one technician assembles each high-performance V8 engine
- Engine lifecycle data record as a new standard in production
- Unsurpassed precision, attention to detail and know-how
The special production techniques used at the Affalterbach location were already taken into account during the development and conceptual work on the new AMG 6.3-litre eight-cylinder engine; these ensure freedom of action and open up new possibilities during the engine design stage.
Assembly of the complex valve train with bucket tappets in the cylinder heads must be done by hand, for example, and that is only possible in the highly specialised environment of the AMG engine workshops.
Approx. 100 AMG high-performance engines assembled per day
It is a tradition at Mercedes-AMG that every engine is built by hand according to the “one man, one engine” philosophy. This means that one technician assembles the entire engine and confirms this by his signature on the AMG engine badge.
The AMG engine shop has three storeys with an effective total floorspace of 9950 square metres and produces around 100 high-performance engines for various vehicle models each day.
Production of AMG engines is geared to the highest flexibility, and can be rapidly adjusted to the current market conditions and order intake.
One AMG technician builds an entire engine, and is responsible for everything from installation of the crankshaft in the engine block, the camshafts and right up to the electrical wiring and the engine oil – clearly witnessed by his signature on the engine badge.
After completion, a technician checks the engine’s operation with simulated resistances and pressure charges on the so-called cold-test bench.
Electronic documentation of the entire production process
The electronic production documentation system known as “AMG Trace” is a completely new feature in the AMG engine shop.
This system provides full documentation of various process parameters such as the tightening torques of all bolted connections, fluid levels, component and batch information and test results.
Special PCs are mounted on the assembly trolleys which have a wireless link to a documentation database. They display the relevant online information depending on the assembly stage.
This state-of-the-art system guarantees exemplary production quality at the highest level. At the same time its unique architecture combines the traditional approach to AMG engine production with the production trends of the future.
Only highly qualified technicians with many years of experience are employed at the AMG engine workshops. The utmost precision and attention to detail are a matter of course during the hand-assembly process – even in peak periods when demand is particularly strong.
All work stages are subject to the stringent Mercedes-Benz quality criteria which also apply to all other series-production engines. After all, even an AMG high-performance engine must exhibit the reliability and long operating life typical of a Mercedes.
Fully automatic high-bay warehouse, ultra-modern data management
Concentration of all the functional areas is a special characteristic of the AMG engine workshops. The resulting, short distances and optimisation of all processes directly benefit the working conditions of all the employees.
The most up-to-date logistics ensure highly flexible and efficient production: after assembly, the AMG engines are automatically conveyed from the ground floor to the high-bay warehouse on the top floor.
More than 1000 engines are stored here, and a state-of-the-art data management system enables the inventory to be continuously optimised, while the current stock levels can be easily obtained at any time.
Since 2004 only powerful V8 and V12 engines for AMG high-performance cars have been produced in the AMG engine workshops.
Reviewing almost 40 years of top performance
- 1971: premiere of the famous 300 SEL 6.8 AMG with the V8 racing engine
- 1986: the 300 CE 5.6 AMG achieves a maximum speed of 300 km/h
- 1993: the C 36 AMG appears as the first cooperation project
- 2001: new AMG 5.5-litre supercharged V8 engine with an output of 368 kW/500 hp
- 2003: the AMG 6.0-litre V12 biturbo engine with 450 kW/612 hp and the 460 kW/626 hp AMG 5.5-litre supercharged V8 engine of the SLR McLaren set new standards
Powerful acceleration, effortless torque, high-tech derived from motorsport and typical Mercedes long-distance comfort – AMG high-performance engines have been providing these for almost 40 years.
These impressive qualities are based on the unique AMG philosophy which governs the design, testing and production of its engines.
AMG was the first company to provide a professional engine customising service for Mercedes-Benz cars, and is acknowledged as the pioneer by the entire industry.
AMG V8 engines have always been in a class of their own. It all started in 1971, with the 6.8-litre, 309 kW/420 hp racing engine in the legendary 300 SEL 6.8 AMG.
At the 24-hour race in Spa-Francorchamps (Belgium) this fast Mercedes saloon immediately secured a highly acclaimed class victory and second place overall.
The powerful eight-cylinder racing engine made AMG known throughout the world overnight. Soon AMG also had a suitable engine available for S-Class customers in search of more power: on the basis of the 184-kW/250-hp V8 engine of the 300 SEL 6.3, the company developed a 206-kW/280-hp eight-cylinder unit which gave the luxury saloon the performance characteristics of a sports car.
The first four-valve Mercedes engine was developed by AMG
Subsequent AMG high-performance engines also provided unprecedented driving pleasure in other Mercedes models. For example the five-litre V8 engine with 203 kW/276 hp, which gave the Mercedes-Benz 280 CE 5.0 AMG a dynamism previously unknown in this vehicle class in 1983.
Just one year later AMG came up with a completely independently developed V8 unit featuring four-valve technology and an output of 250 kW/340 hp – a sensational figure at the time. In 1986 the V8 engine, which had meanwhile been uprated to 5.6 litres and an output of 265 kW/360 hp, gave the 300 CE 5.6 AMG a maximum speed of no less than 300 km/h – as was even reported on the evening television news .
American fans respectfully referred to the fast AMG Coupé as “The Hammer”. The last evolutionary stage of the eight-cylinder powerpack appeared in 1988: from a displacement of six litres the four-valve unit developed a maximum output of 283 kW/385 hp and an unrivalled torque of 566 Newton metres.
Cooperation between Daimler-Benz and AMG with the C 36 AMG
The C 36 AMG appeared in 1993, as the first car jointly produced under the cooperation agreement between AMG and Daimler-Benz AG.
Its 3.6-litre in-line six-cylinder engine developed a maximum output of 206 kW/280 hp. In 1996 the E 50 AMG with a five-litre AMG V8 engine developing 255 kW/347 hp was introduced as the top-of-the-line model in the completely new Mercedes-Benz
E-Class with its distinctive twin-headlamp look. One year later AMG surprised the world with a 4.3-litre V8 engine in the C-Class: the C 43 AMG had an output of 225 kW/306 hp and was also available as an estate model.
In 1997 AMG also presented the newly developed 5.5- litre eight-cylinder engine with three-valve technology and twin-spark ignition.
This was initially designed to give a fulminating performance to the E 55 AMG, but within a short time it was also powering other AMG high-performance cars such as the CLK 55 AMG, ML 55 AMG, SL 55 AMG, S 55 AMG, CL 55 AMG and G 55 AMG.
Uprated to 270 kW/367 hp and 510 Newton metres, it now provides dynamic performance at the highest level in the current models C 55 AMG, CLK 55 AMG Coupé and Cabriolet, as well as the SLK 55 AMG.
AMG engines win the “Engine of the Year Awards” in 2003 and 2004
In 2001 the company’s entry into supercharger technology was marked by the C 32 AMG and the SLK 32 AMG.
Their completely newly developed, supercharged V6 engine developed an output of 260 kW/354 hp. Another milestone in the history of AMG engine development was the 5.5-litre supercharged V8 unit with an output of up to 368 kW/500 hp and 700 Newton metres of torque.
This celebrated its premiere in the SL 55 AMG at the end of 2001, followed by the S 55 AMG, CL 55 AMG, E 55 AMG, G 55 AMG Kompressor and CLS 55 AMG.
At the “International Engine of the Year Awards” in 2003 the AMG 5.5-litre supercharged V8 engine was voted the clear winner.
This victory in the “Best Performance Engine” category against well-established competitors from Europe, Japan and the USA was achieved by a wide margin over the runner-up.
A further development of the supercharged V8 engine with 428 kW/582 hp and a torque of 800 Newton metres powers the CLK DTM AMG of 2004, a limited edition of 100.
The supercharged V8 engine of the Mercedes-Benz SLR McLaren presented in 2003 is a special case: this super sports car is powered by a completely AMG-designed, high-tech eight-cylinder engine with dry sump lubrication.
Its outstanding performance figures: an output of 460 kW/626 hp and 780 Newton metres of torque.
AMG V12 engines with outputs from 525 to 612 hp
AMG can also look back on an impressive tradition where V12 engines are concerned. 1998 saw the appearance of the CLK-GTR, a limited edition of 25 vehicles as the road version of the extremely successful racing car from the FIA-GT Championships.
The four-valve twelve-cylinder engine developed 440 kW/600 hp from a displacement of 6.9 litres. In 1999 the new SL 73 AMG with its 7.3-litre V12 engine (386 kW/525 hp, 750 Nm) made an unprecedented level of dynamism and driving refinement possible.
New dimensions in power characteristics and dynamic performance were opened up by the new AMG 6.0-litre V12 biturbo engine in 2003.
This powerpack offers unrivalled performance, with an output of 450 kW/612 hp and 1000 Newton metres of torque. To reduce the stresses on the powertrain the torque is electronically limited from 1200 to 1000 Newton metres – a record-breaking value.
The AMG V12 engine offered in the S 65 AMG, CL 65 AMG and SL 65 AMG was able to continue the success of the supercharged V8 engine introduced in 2003.
Its exceptional attributes were acknowledged at the 2004 “International Engine of the Year Awards”, where the jury voted it the clear winner of the “Best Performance Engine” category in a field of more than 70 competitors from Europe, the USA and Japan.
AMG C-Class with a V8 racing engine in the DTM series
AMG engines also achieve impressive results on the racetrack. The AMG-Mercedes C-Class racks up victory after victory in the German Touring Car Masters (DTM).
These racing tourers from Affalterbach are powered by 4.0-litre eight-cylinder engines generating around 350 kW/475 hp at 7500 rpm.