Mercedes performance division AMG has just announced its new biturbo V8 engine, making 536-hp and 590 ft-lbs of torque (563-hp and 664 ft-lbs of torque with the AMG Performance Package). Designed to replace the 6.2-liter AMG mill, the M157 engine will first appear in the 2011 S63, where it will also make a decent 22.4 mpg and carry the luxurious beast to 60 mph in just 4.3 seconds. Top speed for the new S63 will be rated at 186 mph when equipped with the AMG performance package. After, Mercedes will begin to use the engine in all of its AMG 63 models, including in the SLS, where it is expected to get even more power.
In the S63, the new V8 Biturbo will use Mercedes’ AMG SPEEDSHIFT MCT 7-speed sports transmission, which first debuted on the SL63. In “M” Manual mode, it will not automatically downshift or upshift, even at redline, to give the drive optimum control.
Torque for the new engine is available at very low revs, with 494 ft-lbs on ta at just 1500 rpm, while 590 ft-lbs are delivered at 2400 rpm. As for the AMG Performance Package models, 645 ft-lbs comes on at 2000 rpm, while 664 ft-lbs starts at 2500 rpm.
Engine highlights include direct-injection with piezo electric injectors and the use of a start/stop system to conserve fuel while the car isn’t in motion in a new Controlled Efficiency mode.
To help showcase the new engine Mercedes has commissioned a special S63 AMG showcar, designed after the 300 SEL 6.8 AMG, which took a class victory and second place overall at the 24-hour race in Spa-Francorchamps in 1971.
GALLERY: AMG Biturbo V8 and the 2011 S63 AMG
Official release after the jump:
“AMG Performance 2015” — new powertrain
with the 5.5-liter V8 biturbo engine
The descriptions and data contained in this press kit apply to the international model range
of Mercedes-Benz. Specifications may vary from country to country.
Powerful and efficient: an eight-cylinder developing up to 563 hp
Aim: Best in class – top performance in all respects by virtue of a comprehensively efficient powertrain
Affalterbach – AMG is writing another chapter in its “AMG Performance 2015″ drive system strategy: a completely newly developed AMG 5.5-liter
V8 biturbo engine with a peak output of up to 563 hp and maximum torque of up to 664 lb-ft. will enter the lineup in late 2010. The new eight-cylinder unit known internally as the M 157 impresses with a wealth of technological highlights such as direct gasoline injection with spray-guided combustion and twin turbochargers.
This innovative, independently developed eight-cylinder power unit from Affalterbach sets new standards in terms of fuel consumption and exemplary efficiency: the 2011 S63 AMG, in which the V8 biturbo will have its market debut, acheives an estimated 22.4 mpg (NEDC combined consumption, provisional figure). An intelligently designed power transfer plays a major part in this: the unique AMG SPEEDSHIFT MCT 7-speed sports transmission combines performance with economy, and includes a new start/stop function in the “Controlled Efficiency” driving mode. The new engine/transmission combination is the epitome of exclusivity, sophistication, high performance and economy.
The S63 AMG showcar is a homage to the impressive history of powerful AMG V8 engines: visually this high-performance sedan resembles the spectacular 300 SEL 6.8 AMG, the racing car that won a class victory and second place in the overall ranking for AMG at the 24-hour race in Spa-Francorchamps (Belgium) in 1971 – and made the company world-famous overnight.
“AMG Performance 2015″ as the continuation of a success story
Mercedes-AMG is continuing this impressive story with its “AMG Performance 2015″ strategy, and meeting its promise to continuously reduce both the fuel consumption and emissions of new models with the new engine/transmission combination – while reaching new heights with the central brand value of “performance”.
The new AMG 5.5-liter V8 biturbo engine will play a major part in the Mercedes-AMG model strategy over the next few years. The unique AMG SPEEDSHIFT MCT 7-speed sports transmission will also guarantee a thrilling yet economical power transfer in future AMG high-performance cars. The new engine/transmission combination is another milestone in the success story of Mercedes-AMG, which began in 1967. Another highlight in the company’s more than 40-year history it undoubtedly the SLS AMG: this gull-wing model due to be launched in May 2010 is the first automobile to be completely independently developed by Mercedes-AMG. It means that as the performance brand within Mercedes-Benz Cars, AMG is not only fielding a masterpiece but also demonstrating development expertise at the highest level.
Direct gasoline injection with spray-guided combustion and twin turbocharging
While the AMG 6.3 liter V8 naturally aspirated engine has a displacement of 6208 cc the new AMG 5.5-liter V8 biturbo unit makes do with 5461 cc. The use of direct injection technology results in a reduction of exactly 747 cubic centimeters and increases efficiency. For the first time, AMG is also utilizing the advantages of direct gasoline injection with spray-guided combustion and piezo-electric injectors: thanks to its higher thermodynamic efficiency, this technology makes more efficient use of fuel and leads to lower exhaust emissions. AMG combines this spray-guided combustion with twin turbochargers. Other highlights include a crankcase wholly of aluminum, four-valve technology with adjustable camshafts, an air/water intercooler, generator management and a start/stop function as standard.
This high-tech package leads to a high output and torque yield, together with fuel consumption figures that are unrivalled in the competitive lineup. The AMG 5.5-liter V8 biturbo engine develops a peak output of 536 hp and maximum torque of 590 lb-ft. In conjunction with the AMG Performance package these figures are increased to 563 hp and 664 lb-ft. A look at the performance diagrams shows that no other engine in this output class achieves the figures delivered by the new AMG biturbo. The major difference between the two performance classes is an increase in the maximum charge pressure from 1.0 to 1.3 bar.
Quantum leap: fuel consumption reduced by 25 percent
With a provisional NEDC fuel consumption of 10.5 liters per 100 kilometers, the new S63 AMG is 3.9 liters more economical than the preceding model powered by the naturally aspirated AMG 6.3-liter V8 – despite an increase in output by
18 hp and in torque by 125 lb-ft. Engine specialists consider this achieved fuel saving of more than 25 percent to be nothing less than a quantum leap. CO2 emissions have likewise been significantly reduced: at 246 grams per kilometer, the figure is 28.5 percent lower than for the previous model.
With figures like these, the new S63 AMG is not only considerably better than all its competitors, but also more fuel-efficient than much less powerful cars in this segment. Taking into account its enormous performance and torque figures the new AMG 5.5 liter V8 biturbo engine is in parts twice as efficient as many mid-segment or compact-class diesel engines.
At the same time the S63 AMG delivers superior performance at sports car level: the high-performance sedan accelerates from zero to 60 mph in 4.4 seconds, and has an electronically limited top speed of 155 mph. The 60 mph mark is reached in just 4.3 seconds with the AMG Performance package, with the top speed increased to an electronically limited 186 mph.
Engine production – tradition of hand-built excellence
Like all other AMG engines, the new eight-cylinder biturbo is assembled by hand in the AMG engine shop taken into commission in 2002. A single, highly-qualified technician assembles the M 157 according to the “one man, one engine” philosophy, maintaining the very strictest quality standards. This painstaking care is
attested to by his signature on the characteristic AMG engine plate.
AMG CEO Volker Mornhinweg: “Efficiency plus performance”
“With the new AMG V8 biturbo engine and the AMG SPEEDSHFT MCT 7-speed sports transmission, we are confronting the challenges of the future and focusing on fuel consumption and exhaust emissions even more intensively than before. Our new high-performance engine shows that AMG occupies a leading position
in terms of both efficiency and our brand commitment to “performance,” says Volker Mornhinweg, Chairman of Mercedes-AMG GmbH.
“The new AMG V8 biturbo engine is yet another milestone in our impressive V8 history. For the first time we have combined spray-guided direct gasoline injection with turbocharging. With this high-tech package we are “best in class” with
respect to fuel consumption, output and torque,” says Friedrich Eichler, Head
of Engine and Powertrain Development at Mercedes-AMG.
Key figures at a glance: *
AMG 5.5-liter V8 biturbo engine
Displacement 5461 cc
Bore x stroke 98.0 x 90.5 mm
Compression ratio 10.0:1
Output 536 hp at 5500 rpm
563 hp) at 5500 rpm**
Max. torque 590 lb. ft. at 2000-4500 rpm
664 lb. ft. at 2500-3750 rpm**
at 2500-3750 rpm*
Engine weight (dry)
* provisional figures; ** with AMG Performance package
Exciting power delivery, characteristic sound
These on-paper figures raise high expectations which the 536 hp AMG 5.5-liter V8 biturbo certainly meets. The flat torque curve ensures enormous pulling power in all speed ranges: 494 lb-ft. are already available at 1500 rpm, and the maximum torque of 590 lb-ft. is delivered just 500 rpm later, remaining constant to 4500 rpm. Even more effortless performance is ensured by the engine variant with the AMG Performance package, which has a peak output of 563 hp. In this case the eight-cylinder delivers 645 lb-ft. of torque at just 2000 rpm, with a constant 664 lb-ft available between 2500 and 3750 rpm.
It is not only the unrivalled torque delivery of this turbocharged eight-cylinder that makes the heart beat faster, as the agile responsiveness with no irritating charger delay leads to an effortlessness and performance previously unknown in this output class. All perfectly matched by the characteristic, sonorous engine note. Moreover, this AMG high-performance engine naturally meets all the
requirements with respect to smooth, quiet running and the comfort on long journeys that is to be expected of a Mercedes.
MCT 7-speed sports transmission with Controlled Efficiency mode and start/stop function
Power is transferred by the AMG SPEEDSHIFT MCT 7-speed sports transmission used exclusively by AMG, which is already familiar from the SL63 AMG and E63 AMG and combines high emotional appeal with outstanding driving dyna-mics and a high level of efficiency. The wet start-up clutch replaces a conventional torque converter, and helps to save fuel. The exemplary fuel economy is also in large measure due to the standard start/stop function. This system is active in the transmission’s Controlled Efficiency (“C”) mode, and switches the eight-cylinder engine off when the car comes to a stop. In “C” mode the sports sedan always starts off in second gear, and the transmission shifts to the next, higher gears at a noticeably early stage. With its high torque at low engine speeds, the V8 engine encourages a smooth, effortless driving style.
The eight-cylinder biturbo engine also features the generator management system familiar from the E63 AMG: whenever the engine is on the overrun or when braking, kinetic energy is used to charge the battery rather than being wasted as heat in the usual way. In all other operating modes a combination of onboard network and generator management enables the generator to be kept at a low voltage. This reduces the load on the engine and makes for fuel savings of around 0.15 liters per 100 kilometers according to the NEDC standard, and up to 0.2 l/100 km in
city traffic with its frequent overrun and braking phases.
Long tradition of powerful AMG V8 engines
Powerful eight-cylinder engines are an integral part of AMG’s history. 2005 saw the debut of the AMG 6.3-liter V8 engine known as the M 156. Depending on the model, this naturally aspirated, high-revving unit develops up to 518 hp and 465 lb-ft. Reserved exclusively for the new SLS AMG, the M 159 with the same displacement of 6.3 liters has a peak torque of 563 hp and maximum torque of 479 lb-ft. Another milestone in the history of AMG engines was the supercharged AMG 5.5-liter V8 engine introduced in 2001: the M 113 K developed up to 500 hp and 516 lb-ft of torque. Even more power was forthcoming from the supercharged AMG 5.5-liter V8 engine of the SLR McLaren dating from 2003 – the M 155 generated up to 617 hp and 575 lb-ft.
The supercharged AMG 5.5-liter V8, the AMG 6.3-liter V8 and the AMG 6.0-liter V12 biturbo were all able to win the Best Performance Engine category in the
International Engine of the Year Awards.
The first AMG four-valve V8 accelerates “The Hammer” to 188 mph
Another important engine in the AMG story was the M 117, its first eight-cylinder unit with four-valve technology. With a displacement of 5.6 liters, 355 hp and 376 lb-ft of torque, this V8 accelerated the 300 CE 5.6 AMG to a top speed of 188 mph in 1987. This made the coupé the fastest German car in series production, and American fans reverently christened it “The Hammer”.
The S63 AMG showcar harks back to the historic success in 1971
A historic success was achieved by the 300 SEL 6.8 AMG in 1971: powered by
an AMG V8 engine with a displacement of 6.8 liters and developing 422 hp, this signal red racing sedan crossed the finishing line in second place during its very first outing at the 24-hour race in Spa-Francorchamps (Belgium), securing victory in its class.
The spectacular S63 showcar is homage to this triumph, which made AMG world-famous overnight although the company had only been founded in 1967: decorated with sponsoring stickers identical to those on its historic predecessor, this powerful S-Class made by Mercedes-AMG is a sensation. The imposing tires in size 275/35 R 20 and 325/30 R 20 at the front and rear are just as eye-catching as the 4.5-centimetre wider front fenders on each side. The discerning car-lover will even discover exotic wood trim in the style of the original car in the interior.
The showcar is powered by the new AMG 5.5-liter V8 biturbo engine and the
AMG SPEEDSHIFT MCT 7-speed sports transmission.
At a glance:
The most important highlights of the new AMG V8 biturbo engine and the new AMG SPEEDSHIFT MCT 7-speed sports transmission
• Direct gasoline injection with piezo-electric injectors and spray-guided
• Twin turbochargers with air/water intercooling
• Sophisticated engine electronics with Controlled Efficiency start/stop function and generator management
• Aluminum crankcase with ventilation holes to reduce friction
• Continuous camshaft adjustment on the intake and exhaust sides
• Demand-controlled engine oil pump
• AMG SPEEDSHIFT MCT 7-speed sports transmission with a wet start-up clutch and three driving modes
Development goals and design
Perfect combination of performance and efficiency
Emotional peak performance and enormous torque, agile power delivery and a characteristic engine sound, comfort on long journeys and hallmark Mercedes reliability: expectations are high when Mercedes-AMG introduces a new high-performance engine – and its very first biturbo eight-cylinder is no exception. Two criteria are continue to gain importance, namely efficiency and economy. Mercedes-AMG is confronting the challenges of the future, and demonstrating that dynamic performance can be perfectly combined with fuel economy.
The new AMG 5.5-liter biturbo engine combines performance with efficiency to a previously unknown extent. This is made possible by a unique combination of innovative high-tech systems such as direct gasoline injection, twin turbochargers, air/water intercooling and the Controlled Efficiency start/stop function. The eight-cylinder biturbo engine will celebrate its market debut in the 2011 S63 AMG in late 2010.
Mercedes-AMG is systematically following the trend towards increasing efficiency with its new V8 biturbo engine: with a displacement of 5461 cubic centimeters it is precisely 747 cc below the 6208 cc of the naturally aspirated AMG 6.3-liter V8. Nonetheless it considerably betters it in terms of output and torque. The AMG 5.5 liter V8 biturbo engine develops a peak output of 536 hp and maximum torque of 590 lb-ft. In conjunction with the AMG Performance Package these figures increase to 563 hp and 664 lb-ft. The torque curve in particular shows that no other engine in this output class is able to match the figures delivered by the new Mercedes-AMG biturbo unit.
Despite an increase in output by 18 hp and in torque by 125 lb-ft. compared to the naturally aspirated V8, which develops 518 hp and 465 lb-ft., AMG engineers have been able to reduce fuel consumption and CO2 emissions considerably.
With a provisional NEDC fuel consumption of only 22.4 mpg, the new S63 AMG achieves a fuel savings of more than 25 percent, which engine specialists consider to be nothing less than a quantum leap. CO2emissions have likewise been significantly reduced: at 246 grams per kilometer, the figure is 28.5 percent lower than for the previous model (344 g/km).
The achievement of these efficiency and environmental aims has no negative
effects whatsoever on dynamic performance. On the contrary, as the new AMG 5.5-liter V8 biturbo fully lives up to AMG’s brand commitment to “performance”: the S63 AMG accelerates from zero to 60 mph in 4.4 seconds, and has a top speed of 155 mph (electronically limited). With the AMG Performance package, the high-performance sedan reaches the 60 mph mark in 4.3 seconds and reaches a top speed of 186 mph (electronically limited).
Key figures at a glance: *
S 63 AMG Mercedes-Benz
S 63 AMG with AMG
Cylinder arrangement V8 V8
Valves per cylinder 4
5461 cc 5461 cc
Bore x stroke
98.0 x 90.5 mm 98.0 x 90.5 mm
106 mm 106 mm
400 kW (544 hp)
at 5500 rpm
420 kW (571 hp)
at 5500 rpm
Output per liter
73 kW (100 hp) 77 kW (104 hp)
800 Nm at
at 2500-3750 rpm
Torque per liter
146 Nm 165 Nm
Maximum engine speed
6500 rpm 6500 rpm
18.5 bar 20.8 bar
Engine weight (dry)
450 lbs. 450 lbs.
22.4 mpg 22.4 mpg
246 g/km 246 g/km
Acceleration 0-60 mph km/h
4.4 s 4.3 s
155 mph** 186 mph**
* provisional figures; ** electronically limited
Combination of twin turbocharging and direct gasoline injection
Mercedes-AMG is presenting an attractive high-tech package with its combination of biturbo charging and direct gasoline injection with spray-guided combustion. The innovative injection technology brings decisive advantages with respect to fuel consumption and exhaust emissions, thanks to higher thermodynamic efficiency. Particularly fast and precise piezo-electric injectors spray the fuel into the combustion chambers, ensuring a homogenous fuel/air mixture and highly effective combustion.
An electric low-pressure pump delivers the fuel from the tank to a high-pressure pump in the trunk with a pressure of six bar. The fuel pressure in the high-pressure rail is controlled between 100 and 200 bar on a fully variable and
Two turbochargers and efficient air/water intercooling
Two turbochargers located next to the cylinder banks supply the eight cylinders with fresh air. At their maximum speed of 185,000 rpm under full load, the two turbochargers force 3,860 lbs of air into the combustion chambers per hour. The maximum charge pressure is 1.0 bar, and 1.3 bar with the AMG Performance
package. Thanks to their specific, compact construction – the turbine housings are welded to the exhaust manifold – there are significant space advantages and the catalytic converters also heat up more rapidly.
The new AMG V8 is the first turbocharged engine to dispense with the usual blow-off valve. This innovative solution enabled the compressor housing to be made extremely compact. To ensure agile responsiveness with no time lag, all the air ducts in the intake tract are as short as possible. The wastegate valve, which
reduces the pressure in the exhaust system during negative load changes, is
vacuum-controlled via an electropneumatic converter. This allows dethrottling under partial loads, which in turn lowers the fuel consumption.
As was already the case in the AMG 6.0-liter V12 biturbo engine, the new eight-cylinder direct-injection unit uses particularly efficient air/water intercooling. The low-temperature cooler with its water circulation is space-savingly accommodated within the V of the cylinder banks. It effectively cools down the intake air compressed by the turbochargers before it enters the combustion chambers, and maintains a constantly low intake temperature under full load. A large radiator
at the car’s front end ensures defined cooling of the water circulating in the low-temperature circuit. This guarantees a high output and torque yield in all ambient temperatures and operating conditions. Extremely short charge air ducting makes for outstanding responsiveness. The stainless steel pressure pipes for the fresh and charge air are produced by the hydroforming process, have a wall thickness of only 0.8 millimeters and are designed for particularly low pressure loss.
Aluminum crankcase with Silitec cylinder liners
The crankcase of the new AMG 5.5-liter V8 biturbo engine is of diecast aluminum. The low (dry) engine weight of just 450 pounds is the result of uncompromising lightweight construction methods, and leads to the car’s very balanced weight distribution. The bearing cover for the main crankshaft bearings is of grey cast iron, and is bolted to the crankcase for high rigidity. Cast-in Silitec cylinder liners ensure that the eight pistons operate with low friction. Drilled pulsation
holes in the crankcase lead to a higher output and fuel savings under partial load: above the bearing blocks there are longitudinally drilled holes which connect
adjacent crankcase cavities. Normally the upward and downward movement of the pistons causes air to be forced into and extracted from the sump, which leads to increased internal friction losses and therefore a reduction in output. The pulsation holes prevent this by ensuring effective pressure compensation between the cavities.
The forged crankshaft of high-grade 38MnS6BY steel alloy rotates in five main bearings, has eight counterweights and has been optimized with respect to torsional rigidity, inertia, low rotating masses and a long operating life. A two-mass viscous damper mounted at the front reliably eliminates vibrations. Each connecting rod journal on the crankshaft carries two forged, cracked connecting rods. In the interests of low mechanical friction and high wear resistance, the lightweight pistons have a metallic contact surface. Pressure-controlled oil-spray nozzles in the crankcase ensure that the highly stressed piston crowns are efficiently cooled.
Four-valve technology with variable camshaft adjustment
Perfect charging of the combustion chambers is ensured by large intake and
exhaust valves, of which there are four per cylinder. The exhaust valves, which are subject to high thermal loads, are hollow and sodium-cooled. Four overhead camshafts operate the 32 valves via low-maintenance, low-friction cam followers. The infinitely variable camshaft adjustment within a range of 40 degrees on the intake and exhaust sides depends on the engine load and engine speed, leading to outstanding output and torque values. This also results in consistent idling at a low speed. Depending on the engine speed, valve overlap can be varied for the best possible fuel/air supply to the combustion chambers and efficient removal
of the exhaust gases.
The variable camshaft adjustment is carried out electromagnetically via four
pivoting actuators, and is controlled by the engine control unit. The camshafts are driven by three high-performance silent chains, which have considerable advantages in noise comfort compared to cylinder roller chains.
Efficient oil supply and water cooling
Efficient oil delivery under all load and operating conditions is ensured by an oil pump with an electrically controlled compression stage. The oil pressure can be varied between two and four bar, which has advantages in terms of friction and fuel consumption. An extraction stage integrated into the oil pump for the two turbochargers prevents oil from being entrained into the charge air and exhaust gases, thereby helping to reduce emissions even further. Both the sump and the extraction point have been optimized for maximum lateral acceleration and
efficient lubrication. The oil capacity is 11 quarts.
The combined water/oil cooling system is a particularly clever solution: initially the engine oil only flows through the oil/water heat exchanger. If the cooling
performance of the very compact cooler is insufficient, the flow is directed through the external engine oil/air cooler by an oil thermostat. The advantage of this system is that the engine oil warms up more rapidly, as the engine coolant warms up faster and the oil is later cooled by the coolant. A selectable water thermostat ensures rapid warming of the coolant when starting the engine and driving off.
The engine coolant is cooled on the particularly effective crossflow principle.
There is a transverse flow of coolant through both the crankcase and the cylinder heads. Additional cooling slots in the cylinder head ensure more efficient cooling of the combustion chambers, which has advantages during combustion: it enables earlier ignition timings to be chosen without incurring the risk of knocking.
Highly efficient engine electronics for every function
All the engine functions are executed and controlled by a particularly efficient Bosch MED 17.7.3. control unit. This state-of-the-art engine computer not only controls the direct gasoline injection, charge pressure, camshaft adjustment and
variable oil supply, but also communicates with all the other onboard control units. The microprocessor has more than 30,000 different parameters and
functions stored in its memory, and is able to perform up to 260 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. Eight high-voltage powerstages are
responsible for highly precise fuel distribution to the piezo-electric injectors.
Effective emissions technology with new catalytic converter boxes
Low exhaust emissions, compliance with country-specific standards and a characteristic AMG engine sound – the requirements for the exhaust system of the new AMG 5.5-liter V8 biturbo engine were numerous and complex. The S63 AMG
complies with all the current EU-5 emission standards, as well as meeting all
the requirements of the US market (LEV-II standard, On-Board Diagnosis II and lambda sensor diagnosis).
The turbochargers are welded to the exhaust manifolds, while air gap-insulated manifolds with a wall thickness of only 1.0 millimeter ensure a rapid catalytic converter response. For efficiency and to save space, this concept has a tandem catalytic converter housing on each side of the vehicle: adjacent to the firewall, two thin-walled ceramic substrates are grouped into each housing. This solution makes the previous, additional underbody catalytic converters unnecessary. The two ceramic substrates differ to ensure rapid and efficient emissions control: the front one is coated with palladium, while the rear one has a bimetal coating of
palladium and rhodium. One lambda sensor per row of cylinders is located in front of each catalytic converter housing, and there is a lambda diagnostic sensor between each of the two thin-walled substrates.
The lambda sensors are necessary for demand-related lambda control. 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 control system.
Twin-pipe AMG sports exhaust system for a characteristic sound signature
The twin-pipe AMG sports exhaust system has a pipe cross-section of 2.7 inches from the manifolds to the rear silencers. When designing the sound, the aim was to create a perfect synthesis of aggressive growl yet comfort on long journeys that is the hallmark of a Mercedes. The goal of the developers was to achieve an emotional experience when accelerating and rev-matching, but unobtrusiveness at constant speeds. Unpleasant frequencies or droning noises were effectively eliminated during a series of painstaking tests. As a result, the striking pair of twin tailpipes of the AMG sports exhaust system emit a sonorous eight-cylinder sound that is typical of AMG.
Power transmission and start/stop function
Intelligent solutions for maximum driving
pleasure and low fuel consumption
Seven gears, three driving modes and a rev-matching function: the power transmission of the 2011 S63 AMG guarantees great emotional appeal and sheer driving pleasure. At the same time the AMG SPEEDSHIFT MCT
7-speed sports transmission makes a considerable contribution to fuel economy – and specifically in combination with the new Controlled Efficiency start/stop function and generator management included as standard features. Accordingly the AMG MCT transmission impresses
with a combination of unique functions which no other manufacturer is
able to offer in this form.
The AMG SPEEDSHIFT MCT 7-speed sports transmission is an innovative power transfer system that made its debut in the high-performance SL63 AMG Roadster in 2008, and has also been in use in the E63 AMG since 2009. It combines the sporty, direct and agile feedback of a manual transmission with the maximum convenience of an automatic transmission. Featuring seven gears, three driving modes and a rev-matching function, the 7-speed sports trans-mission offers superb versatility. MCT stands for Multi-Clutch Technology and indicates that only clutch elements are employed to perform gearshifts.
A wet start-up clutch, which runs in an oil bath, replaces the conventional torque converter. Thanks to its low rotational inertia, the transmission responds instantaneously and dynamically without the losses typical of a torque converter transmission – thereby helping to save fuel. The AMG sports transmission also impresses with its low weight of just 176 pounds, which has been made possible through the use of lightweight magnesium for the transmission housing. Vibrations are effectively eliminated by a new, two-stage torsion damper, with resulting benefits in perceived passenger comfort.
Controlled Efficiency (“C”) driving mode for optimum fuel economy
During its development and adaptation to the new AMG 5.5-liter V8 biturbo
engine, the AMG engineers paid special attention to the new Controlled Efficiency driving mode (“C”). The emphasis was on delivering minimum engine speed coupled with a reduced number of gearshifts in all driving situations. When starting in “C”, the MCT transmission always selects second gear and shifts early to the next higher gears if the driving style permits. At 37 mph, for instance, sixth gear will already be engaged – not only improving fuel consumption but also noise levels. Thanks to its powerful, readily available torque even at low engine speeds, the AMG V8 biturbo unit is absolutely ideal for this style of driving. Controlled Efficiency also means convenient gearshifts and a “soft” accelerator response set-up for outstandingly smooth power transfer.
Controlled Efficiency start/stop function as a new feature at Mercedes-AMG
The Controlled Efficiency start/stop function is also being used in an AMG model for the first time. This system is standard equipment in the 2011 S63 AMG, and permanently active in the fuel economy driving mode “C”. Once the driver comes to a halt e.g. at a red traffic light, the V8 engine is automatically switched off.
Once the brake pedal is released or the accelerator is depressed, the engine is immediately restarted and the car is able to move off quickly. Intelligent techno-logy guarantees a comfortable and immediate starting procedure: a crankshaft sensor which recognizes the direction of rotation registers the resting position of all eight pistons. For an automatic engine start, the cylinder with the most favorable piston position receives an injection of fuel into its combustion chamber. The precise piezo-electric injectors greatly assist this process, as they make particularly fast starts possible.
The engine management ensures that the engine is only switched off if certain preconditions are met. The starter battery must have sufficient charge, for example, and the engine must be at the necessary operating temperature for efficient emissions control. The same applies to the interior temperature selected by the driver: if this has not yet been reached, the engine is not switched off when the car comes to a stop. The onboard network management system makes sure that active audio, telephone or video functions are not interrupted by the start/stop function.
A green “ECO” symbol in the AMG main menu shows the driver that the Controlled Efficiency start/stop function is active. Should one of the above criteria be preventing activation of the system, this is shown in the central display by the message “Start/stop inactive” and a yellow “ECO” symbol. In the two more performance-oriented driving modes “S” (Sport) and “M” (Manual), the start/stop function is always deactivated. If required, the driver can also switch it off while in “C” mode as well.
The eight-cylinder biturbo engine also features the generator management system familiar from the E63 AMG: whenever the engine is on the overrun or when braking, kinetic energy is used to charge the battery rather than being wasted as heat in the usual way. In all other operating modes a combination of onboard network and generator management enables the generator to be kept at a low voltage. This reduces the load on the engine and makes for fuel savings of around 0.15 liters per 100 kilometers according to the NEDC standard, and up to 0.2 l/ 100 km in city traffic with its frequent overrun and braking phases.
Drive modes “S” and “M” for even more driving pleasure and performance
The engine and transmission come across as much more agile in the “S” (Sport) mode. Accelerator pedal movements trigger a more direct traction response,
making the downshifts more spontaneous. The engine speed is allowed to reach a higher level in each gear, while the gearshifts are around 25 percent faster than in “C”. In the manual shift mode “M”, gearshifts at full throttle take just 100 milliseconds, a reduction of 50 percent compared to “C”. In “S” and “M” modes, the engine management system partially suppresses the cylinders: interrupting ignition and injection under full load leads to even faster gearshifts than before. The highly emotional exhaust notes are an appealing side effect of this lightning-fast process.
Ultra-fast, spontaneous multiple downshifts are another forte of the AMG SPEEDSHIFT MCT 7-speed sports transmission. For instance, kickdown allows gearshifts straight from seventh down to fourth gear, or from fifth to second. In the “S” and “M” driving modes the automatic rev-matching function is active. Every manual or automatic downshift is accompanied by precisely metered rev-matching – incrementally from “S” to “M”. And this not only adds to the driver’s emotional experience: the load-free downshift minimizes load-change reactions, which pays particular dividends when braking into bends – and also enhances safety on wet roads or on ice.
No automatic downshifts in manual “M” mode
In manual “M” mode the driver also benefits from the high torque of the V8 biturbo engine, as there is no automatic downshift under full load and kickdown; the transmission remains steadfastly in the selected gear. Moreover, the AMG MCT sports transmission does not perform an automatic upshift in manual mode when the rev limit is reached. In “M” mode the AMG instrument cluster displays the current gear and alerts the driver to the need for an upshift just before the needle reaches the red zone. This means that a particularly sporty driver can use the superior performance potential to its fullest extent. When approaching the lower rev limit, e.g. when braking the vehicle, there is an automatic downshift to the next lower gear. The gears can be shifted using the steering wheel shift paddles – whatever the driving mode. The electronic key for selection of the three driving models is located to the left of the COMAND controller. The powerful electronic transmission control unit with its integrated 80 MHz processor guarantees immediate downshifts – for example when approaching traffic lights or if the driver requires fast acceleration when overtaking.
Development, trials and test bench technology
Endurance testing the exclusive high-tech powerpack
Development work on the new AMG 5.5-liter V8 biturbo engine began in 2006. The program initially involved basic research for a synthesis of top-class performance, powerful torque and potential fuel savings. It quickly became clear that the spray-guided combustion principle exclusively developed by Mercedes-Benz should be combined with twin turbochargers.
The development work on the new eight-cylinder biturbo unit started with fundamental packaging research, analyses of basic mechanical functions, the oil and coolant circuits and the 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 by means of flow simulations and on the dynamic simulation test benches at Mercedes-AMG. Nine of the very latest, high-tech test benches are available in the Mercedes-AMG test bench laboratory, which was taken into commission in 2004; engines with outputs exceeding 1000 hp can be dynamically tested in this facility.
These test facilities are able to simulate any road and environmental conditions to reproduce any conceivable type of operation. Cold or hot starting, mountain passes, stop-and-go traffic or fast laps on the North Loop of the Nürburgring – 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 goal of the detailed bench tests was to verify the performance of all the engine components, including the peripheral units. All the measurement data for the engines examined were systematically compared, and evaluated using reproducible test methods. To ensure the very highest quality standards, the new V8 engines themselves were required to undergo 17,000 hours of endurance testing.
In conjunction with the AMG SPEEDSHIFT MCT 7-speed sports transmission, the final test was a 4000-hour endurance test on a special engine/transmission test bench.
Extensive trials in every climatic zone on earth
At the same time the first test engines had to prove their worth in practical trials. Whether in the icy cold of northern Sweden, the merciless heat of Death Valley (USA), lapping the high-speed circuits in Nardo (Italy) and Papenburg (Germany) or in stop-and-go traffic in inner-city Stuttgart – the standardized test program of Mercedes-AMG includes all climatic zones and route profiles. At the same time it makes the very highest demands on the day-to-day practicality, reliability and long-term durability of the new engine/transmission combination. All in all, the different AMG test vehicles covered around 435,000 miles of mixed endurance testing on the roads.
Special tests for the new start/stop function
The test engineers paid particularly close attention to the operation of the new start/stop function, for which purpose they undertook extended journeys in the stop-and-go traffic of various major cities. This enabled the interaction between the different engine and transmission control units to be painstakingly examined, as well as the influence of the ambient temperature on the operating modes of the new V8 engine. Another major focus was on the vital further development of the control software, and its constantly necessary application to the different onboard systems.
One man, one engine – highly qualified manual assembly in Affalterbach
In contrast to large-series production, every Mercedes-AMG engine is traditionally assembled by hand according to the “one man, one engine” philosophy. A single AMG technician assembles the complete engine in the AMG engine shop in Affalterbach, and is therefore responsible for everything from the installation of the crankshaft in the engine block to the assembly of the camshaft and the cables and oil fill-up – his signature is then put on the engine plate.
The special production techniques used in Affalterbach were already taken into account during the design and development phases for the new AMG 5.5-liter V8 biturbo engine, and this opened up new scope and possibilities with respect to engine design.
Electronic documentation of the entire production process
During the assembly process, each engine undergoes various tests in which it is examined for water and oil leakages. The entire fuel system is also tested for leaks – to the extent that even individual gas molecules can be detected. All the engine functions are then examined on the so-called cold test bench, using simulated resistances and pressurization as well as the very latest resonance
and airborne noise measurement methods. And finally a fully automatic image processing system is used to check the delivery condition of the completed engine.
The assembly process is also controlled and documented by the AMG Trace System. 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.
Assembly of AMG high-performance engines in Affalterbach
The AMG high-performance engines for the different car models are built in the engine shop, which covers an area of 32,000 square feet and occupies two storys. The production procedures are designed for maximum flexibility.
Depending on the order intake, production can be rapidly adapted in line with current market conditions.
Only highly qualified technicians with many years of experience are employed in the AMG engine shop. The utmost precision and attention to detail are a matter of course during the hand-assembly process. 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.