Mercedes-Benz C63 Engine and power transmission
Advanced motoring pleasure and efficiency
The unique drive system in the C 63 AMG Coupé increases its attractiveness: the AMG 6.3-litre V8 engine, with maximum output of 336 to 358 kW and peak torque of 600 Nm, is the embodiment of emotion and dynamism at their very best. The AMG SPEEDSHIFT MCT 7-speed sports transmission combines performance with drive comfort and reduces fuel consumption.
The AMG 6.3-litre V8 engine in the Mercedes-Benz C 63 AMG has been giving drivers excitement and the ultimate in driving enjoyment since 2007. Both have been further heightened in the new C 63 AMG Coupé: this is due in large part to the AMG SPEEDSHIFT MCT 7-speed sports transmission, which made its debut in the SL 63 AMG and is also deployed in, amongst others, the CLS 63 AMG.
The innovative power transmission system has seven gears, four drive programs, a double-declutching as well as a RACE START function. Instead of using a conventional torque converter, a wet start-off clutch has been deployed. Working together with the "Controlled Efficiency" ("C") transmission mode, it helps to achieve laudable consumption figures.
The new C 63 AMG Coupé uses 12.0 litres per 100 kilometres according to NEDC consumption figures – despite its 336 kW output. Output increases to 358 kW in conjunction with the AMG Performance package, yet still the consumption figures remain unchanged.
A glance at the performance figures is enough to show that the C 63 AMG Coupé takes pole position over its competitors. Just 4.4 seconds are needed for acceleration from 0 to 100 km/h; with the AMG Performance package, it takes only 4.3 seconds. The top speed for both variants is 250 km/h (electronically limited).
Key data at a glance:
|C 63 AMG Coupé||C 63 AMG Coupé with the AMG Performance package|
|Valves per cylinder||4||4|
|Displacement||6208 cc||6208 cc|
|Bore x stroke||102.2 x 94.6 mm||102.2 x 94.6 mm|
|Cylinder spacing||109 mm||109 mm|
|Compression ratio||11.3 : 1||11.3 : 1|
|Output||336 kW (457 hp) at 6800/rpm||358 kW (487 hp) at 6800/rpm|
|Output per litre||54.1 kW (73.6 PS)||57.7 kW (78.4 PS)|
|Max. torque||600 Nm at 5000 rpm||600 Nm at 5000 rpm|
|Torque per litre||96.6 Nm||96.6 Nm|
|Maximum engine speed||7200 rpm||7200 rpm|
|Mean pressure||12.8 bar||12.8 bar|
|Engine weight (dry)||195 kg||192 kg|
|Fuel consumptionNEDC combined||12.0 l/100 km||12.0 l/100 km|
|CO2 emissions||280 g/km||280 g/km|
|Acceleration 0 - 100 km/h||4.4 s||4.3 s|
|Top speed||250 km/h*||250 km/h*|
* electronically limited
The AMG 6.3-litre V8 engine - setting pulses racing since 2005
The AMG 6.3-litre V8 engine, with its internal reference code of M156, made its debut back in 2005 and is still viewed as one of the best-performing and torquey eight-cylinder naturally-aspirated engines in series production in the world today. With more than 68,000 units built (as of April 2011), it is the all-time leader as far as AMG engine production is concerned.
The high-revving engine received two awards for best engine at the prestigious "International Engine of the Year Awards 2009": it secured first place well ahead of all other entrants for the "Best Performance Engine" and "Above 4 litres" classes.
Powerful traction at low engine speeds, immediate and effortless response
and exhilarating free-revving: these are just some of the attributes of the eight-cylinder engine which has been designed drawing on over four decades of motorsport experience. A major factor in its overall attractiveness is the role played by the typically AMG sound released from the two chrome twin tailpipes of the AMG sports exhaust system.
Further attributes of the AMG 6.3-litre V8 engine include:
- Torsionally stiff full aluminium crankcase in closed deck design, with a bedplate construction for the lower crankcase section
- Integral oil windage tray to help reduce foaming of the engine oil
- Finely balanced, forged steel crankshaft
- Forged crack connecting rods in lightweight construction
- Lightweight pistons made from a highly durable, ultra heat-resistant alloy
- Piston crowns cooled through pressure-controlled oil-spray nozzles
- Magnesium variable intake manifold with two integral throttle valves to give a steep torque curve and excellent performance
- Vertical intake and exhaust ducts
- Valve control linkage using bucket tappets
- Continuous camshaft adjustment on the intake and exhaust sides
- Engine cooling based on the cross-flow principle
- Variable control of the collant temperature
- Highly effective exhaust gas emission control meeting the EU5 emissions standards
- Engine produced by craftsmen with traditional skills and values whose philosophy is "One man, one engine"
The twin-wire-arc-sprayed (TWAS) coating on the cylinder walls – used exclusively by AMG – produces outstanding low-friction characteristics while reducing fuel consumption. The electronically controlled fuel supply is also highly effective: depending on the power requirements and outside temperature, the system operates at a demand-actuated fuel pressure of between 3.6 and 4.5 bar and is regulated practically instantaneously. The engine management system translates the command from the accelerator within milliseconds into the corresponding fuel pressure setting. Such control ensures rapid vehicle response and sporty acceleration across all load ranges and at all engine speeds.
The AMG Performance package, drawing on SLS AMG technology
An exciting boost to horsepower is available ex factory for the C 63 AMG Coupé: the AMG Performance package increases output from 336 kW to 358 kW, and improves acceleration from 0 to 100 km/h from 4.4 to 4.3 seconds. The reason behind the increase in output of 22 kW is the technology transfer from the SLS AMG. The forged pistons, connecting rods and lightweight crankshaft all originate from the powerful 420 kW AMG 6.3-litre V8 engine known as the M159 for short. The high-tech components from the gullwing model reduce the engine weight by three kilograms and thus help to reduce mass inertia, allowing the eight-cylinder naturally-aspirated engine to react and rev up even more responsively to touches on the accelerator. The distinctive sign of the AMG Performance package is the variable intake manifold finished in titanium grey under the aluminium engine cover.
AMG SPEEDSHIFT MCT 7-speed sports transmission
The best of two worlds – guaranteed by the power transmission of the C 63 AMG Coupé. AMG has deployed the AMG SPEEDSHIFT MCT 7-speed sports transmission in this high-performance vehicle as well: it combines the sporty, direct and nimble responsiveness of manual transmission with the ultimate in comfort of an automatic system. With seven gears, four drive programs, a double-declutching as well as a RACE START function, the MCT transmission excites with its immense emotive appeal, the motoring pleasure
it generates and its unique variability. At the same time, the AMG SPEEDSHIFT MCT 7-speed sports transmission, which is deployed exclusively in Mercedes-AMG vehicles, helps to increase efficiency.
The "C" (Controlled Efficiency) transmission mode is of great importance. During the development and application phases, the AMG engineers paid special attention to two issues: keeping both the engine speed and the number of gear changes as low as possible in all driving situations. When moving off in "C", the MCT transmission always selects second gear and shifts decidedly early to the higher gears if the driving style permits. In town driving, for instance, sixth gear will frequently be engaged – not only improving fuel consumption but noise levels, too. Controlled Efficiency also means convenient gearshifts and a "soft" accelerator response set-up for smooth movement.
The powerful electronic transmission control unit and the integrated 80 MHz processor ensure spontaneous downshifts at the same time – say when approaching traffic lights or if the driver suddenly needs power for dynamic acceleration.
The MCT transmission: lightweight construction and high-tech interior
MCT stands for Multi-Clutch Technology, indicating that gear-changing is executed by clutch elements alone. A compact 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 80 kilograms, which has been made possible through the use of lightweight magnesium for the transmission housing. Vibrations are effectively eliminated by a two-stage torsion damper, with resulting benefits in perceived passenger comfort.
Drive modes "S", "S+" and "M" for driving pleasure and dynamism
The engine and transmission take on a much more agile character in the "S" (Sport) than in the "C" 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. Turning the rotary switch in the centre console a notch further to the right activates "S+" mode. Sport plus shifts the gears another 25 percent faster than in "S". The same applies to the manual shift mode "M". In "S+" and "M" modes, gearshifts at full throttle take just
The engine management system partially suppresses cylinders in "S", "S+" and "M" modes: precisely interrupting ignition and injection under full load for brief periods leads to even faster gearshifts than before. The highly emotional vocals are an appealing side effect of this lightning-fast process.
Double-declutching function, which increases driving enjoyment and safety
Ultra-fast, spontaneous multiple downshifts are another forte of the AMG SPEEDSHIFT MCT 7-speed sports transmission. The driver, for instance, can use kickdown to change directly from seventh gear down to fourth or from fifth to second. In the Sport, Sport plus and Manual modes the automatic double-declutching function is active. Every manual or automatic downshift is accompanied by precisely metered double-declutching – from "S" through "S+" to "M" – which increases incrementally in intensity. And this not only adds to the emotional experience: the load-free downshift minimises load-change reactions, which pays dividends – particularly when braking into a bend on
the racetrack – and also enhances safety in the wet or on ice.
In manual "M" mode, the driver additionally benefits from the high torque of the V8 engine: the transmission remains in the gear selected; there is no automatic downshift under full load and kickdown. 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 central display in the AMG instrument cluster displays the current gear and alerts the driver to the need for an upshift by means of a visual sign: the display colour changes to red and the message "UP" appears. This means that a particularly sporty driver can use the superior performance potential to its fullest extent.
RACE START function: for the ultimate acceleration experience
The driver can choose to change gears using the selector lever or the shift paddles on the steering wheel. To the left of the selector lever is the electronic rotary switch for the selection of one of the four drive programs, including activating the RACE START function. In order to activate it, the driver needs to activate the ESP® sports function and press the brake pedal with his left foot while the vehicle is at a standstill. Having preselected the Race Start program using the rotary switch, a confirmation message comes up on the AMG central display.
The driver then simply needs to confirm the Race Start function by pulling the “Up” shift paddle once, fully depressing the accelerator and taking their foot off the brake. The optimum start-up engine speed is set fully automatically and the C 63 AMG Coupé accelerates away with flawless traction – all the way up to top speed, if so required. The driver does not need to shift gear manually; the AMG transmission changes gear autonomously.