More news on the SLS gullwing!

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The new 'Gullwing' from Mercedes-Benz

Stuttgart/Affalterbach – For the first time in the company's history

stretching back over 40 years, the Mercedes-Benz performance brand

is presenting a vehicle developed in-house, the Mercedes-Benz SLS AMG.

The super sports car serves up an exciting proposition with its unique

technology package: aluminium spaceframe body with gullwing doors,

AMG 6.3-litre V8 front-mid engine developing 420 kW/571 hp peak output

and dry sump lubrication, seven-speed dual-clutch transmission in a

transaxle configuration and sports suspension with aluminium double

wishbones. The ideal front/rear weight distribution of 48 to 52 percent

and the vehicle's low centre of gravity are testimony to the uncompromising

sports car concept.

"Mercedes-Benz is presenting an exhilarating super sports car in the guise of the

new SLS AMG, which is bound to set the pulses of all car enthusiasts racing that

extra bit faster. The SLS AMG is emotion pure and simple for the Mercedes-Benz

brand and is set to become one of the most alluring sports cars of our era", says

Dr. Dieter Zetsche, Chairman of the Board of Management of Daimler AG and

Head of Mercedes-Benz Cars.

"Our customers will experience with the SLS AMG the expertise of our sports car

manufacturer Mercedes-AMG, built up over 40 years of motor racing, along with

the kind of scintillating design that only a top athlete from the Mercedes-Benz

stable can offer", says Volker Mornhinweg, Chairman of Mercedes-AMG GmbH.

The new Mercedes-Benz SLS AMG offers purist, distinctive styling, superior

driving dynamics and hallmark Mercedes everyday practicality and safety. During

the development of the new 'Gullwing', the AMG developers placed their trust in

the valuable know-how of the specialists from the Mercedes Technology Center

(MTC) in Sindelfingen. The aim of this joint development was to turn the SLS AMG

'Gullwing' into the perfect synthesis of the strengths of the Mercedes-Benz and

AMG brands.

Consistent lightweight design thanks to aluminium

The radical design as a highly talented dynamic super sports car with its lowslung

front-mid engine set well back also feeds through into the proportions as

well as the optimised lightweight body concept: for the first time, Mercedes-Benz

and AMG are presenting a car with an aluminium chassis and body. Compared with

the traditional steel design, this results in a significant weight saving, clearly

illustrated in the planned DIN kerb weight of 1620 kilograms excluding driver.

The newly developed bodyshell comprises an aluminium spaceframe. This

exclusive design combines intelligent lightweight design with outstanding

strength – thus delivering superlative driving dynamics. Naturally, the

aluminium spaceframe meets all the requirements in terms of passive safety and

the hallmark Mercedes-Benz body quality that applies to any car sporting the

Mercedes-Benz star. Despite the low sitting position in typical sports car fashion,

the wide-opening gullwing doors make it easy to get in and out of the vehicle.

Fine-tuned AMG 6.3-litre V8 engine developing 420 kW/571 hp

The fine-tuned AMG 6.3-litre V8 engine achieves a peak output of 420 kW/571 hp

at 6800 rpm, thus turning the SLS AMG into one of the most powerful sports cars

in its segment. A power-to-weight ratio of 2.84 kg/hp comes courtesy of the low

vehicle weight. The eight-cylinder naturally-aspirated engine delivers maximum

torque of 650 Nm at 4750 rpm. The 'Gullwing' accelerates from 0 to 100 km/h

in 3.8 seconds, before going on to a top speed of 315 km/h (all figures are

provisional). Bearing the internal designation M159, the V8 high-revving engine

with its displacement of 6208 cubic centimetres has been thoroughly

reengineered compared with the M156 entry-level engine and boasts all the

hallmarks of powerful racing engines.

The principal measures in increasing output include the all-new intake system,

the reworked valve train and camshafts, the use of flow-optimised tubular steel

headers and the dethrottling of the exhaust system. This results in much better

cylinder charging, which feeds through into an increase in output to 420 kW/571

hp with maximum torque of 650 Nm. The eight-cylinder engine responds swiftly

to movements of the accelerator pedal, demonstrating much more

pronounced high-revving flexibility across the entire rev range. The switch to dry

sump lubrication also translates into a much lower position of the engine in the

vehicle. And lowering the vehicle's centre of gravity has also paved the way for

high lateral acceleration and exhilarating driving dynamics.

Perfect synthesis of lightweight design and strength

The use of high-strength components compensates for the increased engine load

associated with the higher output. Forged pistons, a reinforced crankshaft bearing,

optimised crankcase structure, along with improved lubrication thanks to an

on-demand high-performance oil pump ensure optimum durability.

Despite these higher loads, the engine weight for the M159 has been further

reduced. The forged pistons as oscillating masses play a particularly valuable role

in this respect. Thanks to targeted weight optimisation, the weight of the engine

has been reduced further, resulting in a kerb weight of 206 kilograms and, in

turn, a power-to-weight ratio of 0.36 kg/hp. The AMG 6.3-litre V8 engine thus

delivers the best figure by far compared with its competitors.

Sophisticated catalytic converter technology enables current and future exhaust

emission standards such as EU 5, LEV 2 and ULEV to be met. The frictionoptimised

twin-wire-arc-sprayed (TWAS) coating on the cylinder walls – a process

that remains exclusive to AMG – also reduces fuel consumption, as does the

on-demand, map-optimised oil supply along with the regulated generator

management. Thanks to the targeted use of efficiency-enhancing measures,

fuel consumption for the SLS AMG is around 13 litres of Super Plus per

100 kilometres (NEDC combined, provisional figure).

Dual-clutch transmission with transaxle configuration and torque tube

The AMG 6.3-litre V8 engine delivers its abundant power via an ultra-light

carbon-fibre driveshaft at the rear axle – similar to the set-up used on the

DTM C-Class racing touring car. The transmission is mounted at the rear

(transaxle principle) and is connected to the engine housing via a torque tube.

A carbon-fibre shaft rotates at engine speed in the torque tube. The advantages

of this sophisticated solution are associated with the rigid link between the engine

and transmission and, in turn, the optimum support for the forces and torque

generated. A new AMG dual-clutch transmission with seven gears takes care of

power transfer. The transmission boasts fast gear changes with no loss of tractive

force. The driver has a choice of four different driving modes, ranging from

comfortable to extremely sporty, as well as a RACE START function. Optimum

traction comes courtesy of the mechanical differential lock, which is integrated

in the compact transmission casing.

The chosen solution with a front-mid engine plus transaxle configuration ensures

an ideal front/rear weight distribution of 48 to 52 percent. Mounting the engine

behind the front axle has created the ideal conditions for consummate driving

dynamics with precise steering, first-class agility, low inertia with spontaneous

directional changes and outstanding traction. The suspension technology is

also a match for these high standards: wheel location comes courtesy of double

wishbones and hub carriers made of lightweight forged aluminium. The

'Gullwing' comes with 3-stage ESP® as standard, providing the driver with access

to the three "ESP ON", "ESP SPORT" and "ESP OFF" modes at the push of a

button.

Ceramic composite brakes, innovative flow-forming wheels

The AMG high-performance composite brakes all-round ensure extremely short

stopping distances even under enormous loads. The newly developed, optional

ceramic composite brakes with larger brake discs guarantee even better brake

performance and lower unsprung masses. The ceramic brake discs will perform

reliably at even higher operating temperatures thanks to their greater hardness,

all combined with an impressive weight reduction of around 40 percent. Lightweight

design was also a key consideration with the wheels: weight-optimised

AMG light-alloy wheels – 9.5 x 19 inch (front) and 11.0 x 20 inch (rear) – based on

the innovative flow-forming principle reduce the unsprung masses while increasing

driving dynamics and suspension comfort. 265/35 R 19 (front) and

295/30 R 20 (rear) tyres developed exclusively for AMG ensure optimum grip.

The design and development phase for the super sports car got underway in the

last quarter of 2006. The intensive vehicle testing programme will be complete by

the end of 2009. Meanwhile, the reinterpretation of the legendary 'Gullwing' is

scheduled to be launched in spring 2010.

Engine and drive train

Exclusive high-performance eight-cylinder front-mid engine with dual-clutch

transmission in transaxle configuration

Eight cylinders and 6.3 litres of displacement with a front-mid engine

configuration, high-revving concept, dry sump lubrication and poweroptimised

intake and exhaust system: AMG has developed an impressive

powerplant for the new 'Gullwing', which transports the super sports car

into the top end of the output range. With peak output of 420 kW/571 hp,

the AMG 6.3-litre V8 engine sets new standards, becoming the world's most

powerful standard-fit eight-cylinder naturally-aspirated engine. Thanks to

the targeted use of fuel-efficiency measures, fuel consumption of around

13 litres Super Plus per 100 kilometres (NEDC combined, provisional figure)

has been achieved. Power transfer in the SLS AMG is handled by a new AMG

dual-clutch transmission with seven gears, which is mounted at the rear in

transaxle configuration and rigidly connected to the engine via a torque

tube.

420 kW/571 hp peak output at 6800 rpm and 650 Nm torque at 4750 rpm – the

new high-performance eight-cylinder engine in the Mercedes-Benz SLS AMG

impressively demonstrates the potential of the AMG 6.3-litre V8 engine unveiled

in 2005 with the designation M156. Based on the M156, which develops

386 kW/525 hp and 630 Nm in the SL 63 AMG for instance, the new M159

eight-cylinder naturally-aspirated engine has been radically improved.

The principal changes relate to the intake and exhaust system, oil supply and

crank mechanism. Over 120 parts and components have been redesigned – all

based on the valuable insights gleaned from over 40 years of motor racing.

In design terms, the M159 – like its stablemate the M156 – is a completely

autonomous development. The combination of high-revving concept and large

displacement combines the best of both worlds: exhilarating high-revving

flexibility accompanied by high pulling power at low engine speeds. The new AMG

V8 for the 'Gullwing' delivers 545 Nm to the crankshaft as low down as 2500 rpm,

while the maximum 650 Nm is on tap at 4750 rpm – more than any

other naturally-aspirated engine in this output and displacement class. This

means the eight-cylinder engine promises dynamic acceleration, instantaneous

pickup and sheer driving pleasure at the highest level, just as it does everyday

relaxed motoring.

Key data at a glance:

Cylinder arrangement V8

Cylinder angle 90°

Valves per cylinder 4

Displacement 6208 cc

Bore x stroke 102.2 x 94.6 mm

Distance between cylinders 109 mm

Compression ratio 11.3 : 1

Rated output 420 kW/571 hp at 6800 rpm

Output per litre 67.6 kW/92.0 hp

Max. torque 650 Nm at 4750 rpm

Torque per litre 104.7 Nm

Maximum engine speed 7200 rpm

Mean pressure 13.16 bar

Weight (dry) 206 kg

Power-to-weight ratio 0.36 kg/hp

Optimised cylinder charging thanks to redesigned intake airflow

Optimised cylinder charging represents a key element in the increased output

and torque. The recalculated, improved aerodynamic design of the intake airflow

reduces pressure losses, while the all-new valve train improves the gas dynamics.

The fully reworked magnesium intake manifold comes with perfectly matched

variable resonance tube lengths. Eight velocity stacks, each 290 millimetres long

and 51.5 millimetres in diameter, route the fresh air to the combustion chambers.

Two electronically operated throttle flaps – each measuring 74 millimetres in

diameter –, which are adjustable within fractions of a second, sit behind the new

air filters with a volume just under 9500 cubic centimetres: they can be opened

to their maximum in just 150 milliseconds. The result is exhilarating

responsiveness. Two hot-film air mass sensors located behind the air filters

provide the engine electronics with the necessary information about the

temperature and density of the intake air.

Another special feature of the 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 permits a stiff

valve train and therefore high engine speeds with large valve opening crosssections,

which, in turn, boosts output and torque. The large intake valves have a

diameter of 40 millimetres, while their opposite numbers on the exhaust side

measure 34 millimetres. Unlike the racing engine, a maintenance-free valve train

with hydraulic valve clearance is fitted.

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 electrohydraulically and monitored by the

engine management system.

New exhaust system with two headers

The exhaust system has also been redesigned to optimise output: headers with

precisely tailored tube lengths – likewise adopted from the world of motor

racing – deliver a substantial increase in output and torque thanks to improved gas

cycles. The large tube cross-sections in the newly developed, twin-pipe exhaust

system effectively reduce the exhaust gas backpressure. Two relatively small

centre silencers on the underbody and a large, transverse-mounted rear silencer

help ensure optimum weight distribution.

Two backpressure-optimised bulkhead ceramic catalytic converters mounted

directly on the header and two metal catalytic converters on the underbody

ensure effective emission control and compliance with all current emission

standards such as EU 5, LEV 2 and ULEV. The new AMG engine also comfortably

meets the specific requirements of the U.S. market as well as On-Board Diagnosis

II and oxygen sensor diagnosis.

Dry sump lubrication lowers the vehicle's centre of gravity

The engine position was a critical factor in the technical design of the SLS AMG.

According to the specifications, the engine had to be as low and as far back as

possible to keep the vehicle's centre of gravity low and ensure balanced weight

distribution between the front and rear axle. The solution of fitting the eightcylinder

front-mid engine behind the front axle and combining it with a

transaxle, results in a front/rear weight ratio of 48 to 52 percent.

The much lower position of the V8 engine results from the switch to the dry sump

lubrication system, which does away with the otherwise necessary oil pan. The

dry sump lubrication for the M159 comprises a suction pump, a pressure pump

and an external 5-litre oil reservoir fitted in front of the engine. 13.5 litres of

engine oil circulate throughout the entire system. The oil suction pump draws the

oil directly from the crank chambers and the cylinder heads and pumps it to the

external oil reservoir at a maximum rate of 700 litres per minute. The churning

losses normally associated with immersing the crankshaft in the oil sump in the

oil pan can be prevented by efficiently drawing off the engine oil, thus further

improving the effectiveness of what is nonetheless a very efficient engine.

The hydraulic oil pump, designed as a pendulum-slide vane pump, transports the

oil from the external oil reservoir back into the engine, thus ensuring reliable

engine lubrication even with the kind of high lateral acceleration commonly

experienced on a private racing circuit. The demand-driven hydraulic oil pump

takes its cue from the engine revs as well as temperature and load maps stored in

the control unit. All of which lessens power loss within the engine, resulting in a

substantial reduction in fuel consumption. The front wheel arches house two large

radiators with a blower fan integrated on one side to effectively cool the engine

oil.

Outstanding strength and optimum lightweight design also with the engine

Another innovation comes in the guise of the eight forged pistons that are

0.5 kilograms lighter than the cast pistons on the M156 entry-level engine.

Pressure-controlled oil spray nozzles in the crankcase ensure optimal cooling of

the highly stressed piston crowns. Another targeted weight reduction measure

dispenses with steel liners to house the crankshaft main bearings. The crankcase on

the M159 is made entirely of aluminium, weighing around 4 kilograms less than its

counterpart on the M156. Aluminium bolts are also extensively used on the

M159 to further reduce weight. Compared with steel bolts, this saves around

0.6 kilograms. The AMG 6.3-litre V8 engine weighs 206 kg (dry); this results

in a first-class power-to-weight ratio of 0.36 kg/hp.

In typical motor racing fashion, the crankcase uses a rigid bedplate design on the

closed-deck principle. The engine block and cylinder heads are cast from

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 on the M159 – as was also the case with the M156 – to

produce a tribologically optimal surface, namely a coating applied by twin wire

arc spraying (TWAS). The advantages of this TWAS technology patented by AMG

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 AMG V8 engine are twice

as hard as conventional cast iron liners – a quantum leap for engine specialists.

[Guest Sareve]

Other high-tech components and systems adopted from the M156 include:

the finely balanced crankshaft made out of forged steel;

the water cooling system for the cylinder head using the highly thermal

efficient cross-flow principle familiar from racing engines;

variable coolant control for optimum efficiency;

the computer-controlled fuel supply with fuel pump integrated in the tank.

Powerful cooling module with weight-optimised design

Water cooling comes courtesy of a large cooling module mounted behind the

radiator grille. The cooling module also includes the air conditioning condenser

and the power-steering oil cooler. This innovation is particularly beneficial since it

reduces weight by around 4 kilograms compared with previous components –

while also increasing performance. A large suction-type fan placed directly behind

the cooler expels the hot air as required.

Powerful control unit also provides generator management

The Bosch ME 9.7 AMG engine management system also provides generator

management – another system that helps reduce fuel consumption. Sensors

monitor the charge status of the vehicle battery and reduce the generator output

as soon as the battery is sufficiently charged. To recharge the battery, the system

specifically utilises the engine's overrun phases. The braking energy is converted

into electric energy by means of recuperation.

Through the specific combination of fuel-efficiency measures, NEDC combined

fuel consumption of around 13 litres Super Plus per 100 kilometres is achieved

(provisional figure) – a first-class figure. Ultimately, the new SLS AMG is among

the most powerful super sports car in its segment.

Engine production at the Affalterbach location

The new V8 powerpack for the 'Gullwing' is produced at the ultra-modern AMG

engine workshops, according to the "one man, one engine" philosophy. That

means the each complete engine is assembled by hand from start to finish by a

single engineer. Every day the AMG engine manufacturing facility with its three

floors covering 9950 square metres produces around 100 high-performance

engines for a range of vehicle models.

AMG seven-speed dual-clutch transmission with RACE START

The new AMG dual-clutch transmission with seven gears, four driving modes and

RACE START function is the ideal partner for the powerful eight-cylinder naturally

aspirated

engine. The strengths of this technology, which originated from the world

of motor racing, include spontaneous gearshifts with no loss of tractive force, the

tailored-made control strategy and the supreme ease of shifting. Specially designed

for the high-revving characteristics of the AMG 6.3-litre V8 engine, the dual-clutch

transmission delivers optimum gear ratio adjustment with a close-ratio

configuration. This means that the new transmission provides the 'Gullwing' driver

with even more dynamic acceleration for maximum driving pleasure.

AMG DRIVE UNIT with fully automatic RACE START function

The AMG DRIVE UNIT is the central control unit for the dual-clutch transmission

and all dynamic handling control functions. On the left next to the selector lever is

the electronic rotary switch for selecting the four driving modes, including

activating the RACE START function. This function allows the driver to call on

maximum acceleration potential and ensures optimum traction to the drive

wheels. The optimum start-off engine speed is set fully automatically and the

'Gullwing' accelerates instantly with its electronically controlled wheelspin – as

an option also up to the top speed. The driver does not need to perform manual

gearshifts; the transmission changes the gears with incredibly short shift times.

Four driving modes for maximum driving pleasure and ride comfort

The dual-clutch transmission supports upshifts under full load both in automatic

mode, and manual mode where the gears can be shifted using the AMG shift

paddles on the steering wheel. Four driving modes for maximum driving pleasure

and ride comfort are available: "C" (Controlled Efficiency), "S" (Sport), "S+" (Sport

plus) and "M" (Manual). In "C" mode, the car always moves off in second gear,

while delivering highly efficient gearshifts. In "S" mode, the engine speed is

allowed to reach a higher level in each gear; the downshifts also feel more

spontaneous. The gearshifts are around 20 percent faster than in “C” mode.

Switching to “S+” mode cuts another 20 percent off shift times, while “M” is the

sportiest mode: here the AMG 6.3-litre V8 engine has even more bite, added to

which the AMG dual-clutch transmission shifts gear another 10 percent faster – a

reduction of 50 percent compared with “C” mode. In “M” mode, the transmission

shifts gear in under 100 milliseconds.

Automatic double-declutching function for even more exhilaration

The automatic double-declutching function is active in "S" (Sport), "S+" (Sport

plus) and "M" (Manual) modes. Every manual or automatic downshift is

accompanied by precisely metered double-declutching – from “S” through “S+” to

“M” incrementally. And this not only adds to the driver's emotional experience:

the virtually 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.

The new AMG dual-clutch transmission offers outstandingly compact dimensions

and low weight of just 136 kilograms including the differential. The aluminium

design and the absence of a conventional torque converter improve efficiency and

help considerably reduce fuel consumption. The transmission casing also includes

the mechanical differential lock with its decidedly sporty set-up that pushes driving

dynamics to the limit.

Torque tube with carbon-fibre driveshaft between the engine and

transmission

The dual-clutch transmission forms a fixed unit with the V8 engine via the torque

tube. Engine and the transmission mounted at the rear axle – known as a

transaxle – are connected to each other to ensure flexural and torque rigidity and

to support each other. All of which translates into decisive advantages in terms of

driving dynamics and ride comfort since this sophisticated solution provides a

backlash-free drive train. The 1.64-metre-long torque tube comprises a one-piece

aluminium sand-cast casing and weighs less than 25 kilograms. A driveshaft

rotates inside the tube at the engine speed. As with the Mercedes-Benz C-Class

DTM racing touring car, the shaft is made out of carbon fibre. A key advantage of

this high-tech material: despite its high strength, the carbon-fibre shaft tips the

scales at just 4 kilograms. Consequently, the 1.71-metre-long driveshaft, which

has to transmit 650 Nm torque from the engine to the dual-clutch transmission, is

around 50 percent lighter than a steel equivalent.

The torque tube also accommodates a specially developed torsion damper, which

reliably eliminates noise and vibration, thus optimising ride and noise comfort.

Suspension and braking system

Uncompromising high-tech from motor racing for consummate racetrack performance

Technology from motor racing – whatever applies to the complete drive train

on the new Mercedes-Benz SLS AMG, holds equally true for the suspension

and braking system. The aluminum double-wishbone suspension is tailored

to consistent lightweight design and superb driving dynamics. The AMG

high-performance braking system is also available as an option in an all-new,

high-performance ceramic version.

The commitment of Mercedes-Benz and AMG to building an alluring super sports

car that combines consummate racetrack performance with hallmark Mercedes

long-distance comfort has given rise to an ingenious suspension layout. All four

wheels are located on double wishbones with a track rod, a technology that has

proven itself in motor racing, right through to Formula 1. With a double-wishbone

axle, the wheel location and suspension function remain separate; the

spring/damper struts are supported on the lower wishbone. The double-wishbone

concept with its high camber and track rigidity positively locates the wheel with

minimal elastic movements, providing the driver with an optimum sense of road

contact when driving at the limits.

The kinematics is determined by the different length of the wishbones, the

position of the wishbone link points on the chassis and the position of the steering

knuckles or hub carriers. The wide base of the wishbones channels the wheel

forces to the rigid steel subframe at the front and to the compact, rigid bodyshell

cast nodes in the rear structure.

Wishbones, steering knuckles and hub carriers at the front and rear are made

entirely from forged aluminium – substantially reducing the unsprung masses;

this configuration also notably improves the suspension response.

Long wheelbase and broad track width

The long wheelbase of 2680 millimetres not only results in outstanding straightline

stability but also low wheel load shifts, significantly reducing the vehicle's

tendency to dive and squat. The broad track width – front 1679, rear 1649

millimetres – ensures lower shifts in the wheel loads from the inner to the outer

wheel when cornering, enabling the tyres to retain more grip. The large caster

angle of 11.5 degrees significantly increases negative wheel camber when

cornering and also improves tyre grip – this also ensures outstanding stability

when braking heavily while cornering.

Weight-optimised flow-forming AMG light-alloy wheels

As befits the weight-optimised suspension design, AMG light-alloy wheels are

used that are manufactured using the innovative flow-forming process. As part of

the production process, so-called hot forming in the region around the rim well

compresses the structure, thus improving durability. This enables reduced wall

thicknesses to be used. A weight saving of around 1.1 kilograms per wheel

compared with conventional light-alloy wheels reduces the unsprung masses and

further optimises driving dynamics and suspension comfort.

The AMG light-alloy wheels measuring 9.5 x 19 inches (front) and 11.0 x

20 inches (rear) are shod with 265/35 R 19 (front) and 295/30 R 20 (rear) tyres.

The tyres developed exclusively for the AMG super sports car provide optimum dry

performance on a par with today's 'Cup' tyres – without demonstrating their

inherent disadvantages in the wet and cold. A tyre pressure monitoring system is

fitted as standard to permanently monitor tyre pressure in all four wheels;

individual tyres are shown on the display.

Power-assisted rack-and-pinion steering for consistently direct steering feel

The rack-and-pinion steering gear provides a consistently direct steering feel with

a constant mechanical ratio of 13.1:1, in tune with the high expectations placed on

a super sports car. The power steering provides speed-sensitive assistance and

improves the feedback for the driver as the road speed increases: an

indispensable factor for high-speed straight-line driving. Mounting the steering

gear in front of the engine on the integral subframe enables the engine to be set

down very low.

AMG high-performance composite brakes all-round

High deceleration, precise pedal feel, perfect resistance to fading and superior

safety reserves – the AMG high-performance braking system on the 'Gullwing'

offers all these features. All-round internally ventilated, grooved and perforated

brake discs measuring 390 x 36 millimetres (front) and 360 x 26 millimetres (rear)

provide the ultimate in deceleration. In typical AMG style, this super sports

car only uses brake discs featuring composite technology that has been tried and

tested in motor racing. This sophisticated technology, based on a floating radial

and axial mount between the grey cast iron discs and aluminium bowls using

stainless-steel composite elements, provides superb heat dissipation along with

optimum fade resistance, even in the harsh environment of circuit operation.

The use of aluminium also reduces weight, which has clear benefits particularly

with the brakes in terms of agility and suspension response, thanks to the

substantial reduction in unsprung masses. Six-piston fixed callipers at the front

and four-piston fixed callipers at the rear permit generous brake lining surfaces

of 2 x 120 cm2 and 2 x 58 cm2 respectively. The AMG high-performance braking

system generates braking power of 816 kW/1109 hp under full braking power

from 250 km/h to zero.

All-new ceramic composite brakes as an option

All-new AMG ceramic composite brakes are available as an option – instantly

recognisable with their gold-painted brake callipers with the "AMG Carbon

Ceramic" logo. Thanks to the special materials and production technology used to

manufacture the discs from carbon-fibre-reinforced ceramic in a vacuum at

1700 degrees Celsius, the ceramic discs are much harder. This not only increases

the service life many times over compared with a grey cast iron disc, but also

their resistance to extreme loads and heat. The result: extremely short stopping

distances, exact pressure point and much higher fade resistance even under

extreme operating conditions. The larger ceramic discs – front: 402 x

39 millimetres; rear: 360 x 32 millimetres – also feature a composite design and

are connected with a floating radial mount to an aluminium bowl. Their braking

power of 823 kW/1120 hp during an emergency stop from 250 km/h to zero is

again higher than the AMG composite brake system.

Compared with the conventional composite brake discs, the ceramic brake discs

are 40 percent lighter. The further reduction in unsprung masses not only boosts

driving dynamics and agility but also improves steering response as well as ride

comfort and contact characteristics. Six-piston fixed callipers are fitted at the

front with a brake lining surface of 2 x 154 cm2; four-piston fixed callipers with a

brake lining surface of 2 x 73 cm2 are used at the rear.

Powerful anti-lock braking system and 3-stage ESP®

Standard equipment for the braking system includes an anti-lock braking system

with dynamic brake force distribution. A yawing moment is generated when

braking on bends, which counteracts the vehicle's yaw and stabilises it. The

braking system uses the data supplied by the ESP® sensors in order to identify

such situations reliably.

The Electronic Stability Program has been designed as a highly individual 3-stage

ESP® with Sport function. Tuned consummately for high driving dynamics, the

3-stage ESP® offers three different settings. The ESP® button in the AMG DRIVE

UNIT allows the driver to select between the three modes - "ESP ON","ESP SPORT"

and "ESP OFF" – the currently active mode is shown in the AMG

instrument cluster display. In "ESP ON", the onset of handling instability leads to

braking intervention at one or more of the wheels, accompanied by a reduction in

engine torque.

Briefly pressing the ESP® button activates "ESP SPORT". In this mode the braking

intervention to counter oversteer or understeer, as well as the accompanying

reduction in engine torque, allows a higher dynamic threshold and, for instance,

corresponding drift angles. The full ESP® Sport function is restored as soon as the

brake pedal is operated.

Pressing on the ESP® button for longer activates "ESP OFF". There is no

intervention to control the handling dynamics and no reduction in engine torque.

"ESP OFF" should only be used by experienced drivers on dedicated racetracks. In

this mode too, operating the brake pedal restores all the normal ESP® functions.

The system's traction logic of the acceleration skid control system (ASR) is active

in all three ESP® modes. If one of the drive wheels starts to spin, specific brake

pressure is applied to improve traction notably – especially in conjunction with

the standard-fit mechanical multi-disc limited-slip differential, which generates a

locking factor of 30 percent under load and 60 percent under deceleration. This

means that the engine power is transferred to the road even more effectively

when driving in a particularly dynamic style.

Body

Consistent lightweight design for outstanding driving dynamics and sports car prowess

The Mercedes-Benz SLS AMG has been developed from the ground up. The

'Gullwing' has no predecessor and shares little in common with any other

Mercedes model series. The specification essentially set out to combine

superlative driving dynamics with hallmark Mercedes safety. The

241-kilogram lightweight aluminium spaceframe plays a crucial role in

achieving this goal. For the first time, the outer skin as well as the complete

bodyshell structure have been made entirely out of aluminium – a new

milestone for Mercedes-Benz and AMG.

Aluminium has been used more systematically than ever on the new 'Gullwing'.

Maximum longitudinal and lateral dynamism and superb steering precision have

been achieved not just with an ultra-light yet extremely rigid structure – the best

possible conditions for the material aluminium. Optimum static and dynamic

flexural and torsional rigidity also plays an important role, along with

channelling and transferring extreme longitudinal and lateral forces from the

drive train and chassis. The aluminium spaceframe comprises cast aluminium

components and aluminium sections. Cast components are used at the force nodes

or in areas with high levels of function integration – in other words, wherever high

forces need to be transferred or where large components, such as the gullwing

doors or the dashboard, are attached.

The cast components offer the advantage of specific dissipation of forces and the

opportunity of tailoring the wall thickness locally and individually to load

requirements. As a result, higher stiffness required at certain points, such as at

the suspension connection points, can be realised. Furthermore, each point of a

component only needs to be as thick as necessary, saving weight in areas subject

to minimal loads.

Topology optimisation has enabled the cast components to be fine-tuned specifically

in terms of weight: ribbed structures run exactly in the load

directions; in areas subjected to lower loads, the wall thickness is minimised.

Take for example the roof side member: this highly stressed yet weight-optimised

cast aluminium component forms the structural load path between the front and

rear roof frame, while being used at the same time to anchor the hinges for the

gullwing doors.

Torsionally stiff structure weighing just 241 kilograms

Lightweight aluminium sections connect the force nodes to a sturdy structure.

The large, low-set cross-sections of these aluminium sections ensure high

resistance torque, thus providing the required direct transfer of drive, braking

and suspension forces. The structure prevents unwanted flexibility; the vehicle

responds rigidly, almost without twisting and directly.

45 percent of the intelligent, weight-optimised aluminium spaceframe is made out

of aluminium sections, 31 percent out of aluminium sheet, 20 percent out of

aluminium cast and 4 percent out of steel. Maximum occupant safety requires the

use of ultra-high-strength, heat-formed steel in the A-pillars. The bodyshell weighs

241 kilograms – an absolute benchmark in the super sports car segment when

compared with the peak output of 420 kW/571 hp.

[Guest Sareve]

Low centre of gravity and transverse reinforcing struts for superb dynamism

The entire vehicle concept has been designed to achieve a centre of gravity that is

as low as possible. This applies both to the low connection of the drive train and

axles as well as to the arrangement of the stiffness-relevant bodyshell structure,

which has been kept as low as possible. Examples include the rigid flexural and

torque connections between the front and rear section and the safety passenger

cell, which have been realised consistently using force paths that are as low as

possible. This results not only in a low centre of gravity but also a harmonious

and, thus, efficient force path in the vehicle structure.

Another prominent feature of the uncompromising lightweight construction

design is the transverse reinforcing struts at the front and rear axle that are

integrated into the bodyshell structure. The sections connect the side members

precisely where the highest forces act upon the bodyshell under dynamic

cornering. The advantages of this sophisticated solution include unrivalled

transverse rigidity and the absence of heavy secondary stiffening or supports.

Maximum safety with hallmark Mercedes quality

The new 'Gullwing' also meets the very high standards of passive safety

traditionally found on Mercedes-Benz vehicles. Consequently, the aim of

lightweight design plus outstanding crash performance was geared from the outset

to the vehicle's low centre of gravity and the optimum routing of force and load

paths. The crash load paths are specifically routed around the passengers – this

applies both to front, rear-end and side collisions as well as to roof impacts.

The types of accidents that occur under real conditions formed the basis for the

entire bodyshell design: for instance, the continuous side member runs from the

front cross-member to the side skirt and routes the impact energy into the

extremely rigid sill structure in a frontal collision. Upshot: the passenger cell

does not deform during the standard frontal impact tests. A typical feature of the

'Gullwing' is the engine arrangement as a front-mid engine. Its position behind

the front axle creates a large deformation zone in front of the engine. This in turn

enables a reduced weight bulkhead to be fitted, since it needs to absorb far less

energy in the event of a frontal crash than on a vehicle with a conventional

engine position. The torque tube, which connects the engine to the dual-clutch

transmission located at the rear axle, also improves crash safety: both in the case

of a frontal and rear-end collision, the torque tube takes the stress off the

bodyshell structure because it can specifically absorb and transmit impact

energy.

Sophisticated computer simulations helped optimise all the structure

components. To make doubly sure, over 1000 computer-simulated complete

vehicle crash tests were conducted. The aim was to achieve outstanding crash

performance with low weight. The relevant structural cross-sections were

dimensioned for all the load paths in line with load considerations. Variables

included the geometric design of the load paths and the selection of the most

suitable aluminium alloys for each component in terms of energy absorption,

stiffness and strength. At the same time, the selection of optimum bonding

technology and the consistent stipulation of wall thickness for each component,

taking into account loads when driving and during a crash, were also crucially

important.

State-of-the-art restraint systems with eight airbags

The state-of-the-art restraint systems provide the perfect complement to the hightech

body structure. Occupants in the SLS AMG enjoy standard-fit three-point seat

belts with belt tensioners and belt force limiters. This equipment is rounded off

with eight airbags: two adaptive airbags for the driver and front passenger, a

kneebag for the driver and front passenger, two sidebags integrated in the seats

and two separate windowbags deployed from the door waist rail.

During development, the super sports car underwent over 35 crash tests;

additional component tests were carried out as a double check. The new Mercedes

sports car naturally meets all specific national impact configurations required for

certification. Added to which are all the existing ratings and consumer tests as

well as the particularly demanding in-house crash tests, some of which push the

car far beyond any applicable legal requirements. Each vehicle must pass all these

tests before receiving the highest accolade of vehicle safety: the Mercedes star.

Exclusive hand-built production

The aluminium spaceframe and body are hand-built in compliance with the most

stringent quality standards. Highly qualified specialists put together the

aluminium components using cutting-edge techniques. Depending on

requirements, a suitable joining technology is used – rivets, bonding, soldering

and bolts. And just as you would expect from a new Mercedes-Benz car: the

highest precision during production guarantees optimum production and product

quality.

Design and development

Virtual and real – digital and genuine prototypes promote the highest standards

For the first time in its 40-year-plus history, Mercedes-AMG GmbH has

assumed full responsibility for the design and development of a completely

new vehicle. The experience gained in over four decades of motor racing, plus

the huge know-how in building top-class performance cars as well as joint

development with selected Mercedes-Benz development departments at the

Mercedes Technology Center (MTC) in Sindelfingen provide absolutely solid

foundations for this undertaking.

Exhilarating driving dynamics and hallmark Mercedes everyday practicality –

these attributes are a core part of the specification for the Mercedes-Benz SLS

AMG. The Mercedes-AMG specialists at the Affalterbach location turn to cuttingedge

simulation programmes and extensive test drives across all continents to

realise these ambitious objectives. The design and development of the new super

sports car was approved at the end of 2006.

Before the first 'genuine' prototype is produced, the virtual prototypes must first

get up to speed. The new 'Gullwing' was initially brought to life on the computer –

as a digital prototype (DPT). Painstaking analysis helps determine how the

objectives for the new super sports car can be met. Whether it is weight

distribution, engine position, centre of gravity, suspension design, driving

dynamics, aerodynamics, ergonomics, crash performance or production process –

state-of-the-art simulation programmes enable the vehicle and all its characteristics

to be modelled realistically. The digital prototype is thus a complete virtual car.

Digital prototype provides the basis for initial development prototypes

The digital prototype also helps to plan and develop the first ready-to-drive

development prototypes, in other words cars that are fitted with the first

engineering components such as engine, brakes or suspension, the so-called

mulettos. Thanks to the virtual preliminary work, the test vehicles used since

spring 2007 were already highly mature from the off. State-of-the-art

measurement systems in the vehicles provide useful data, such as the temperature

of the engine oil, coolant and brake discs – the focus, however, may also be on lap

times, such as on the North Loop of the Nürburgring, as well as measureable,

precisely defined driving dynamics manoeuvres to compare various axle

kinematics variants, or spring and damper variants.

Since summer 2008, the first 'genuine' camouflaged prototypes of the SLS AMG

have been undergoing testing around the world. Whether it is the air conditioning

system, tyres, suspension, engine cooling system, dynamic handling control

systems or brakes: the meticulous standardised AMG development and testing

programme on test circuits and racetracks, Alpine passes and specifically defined

public roads promotes consistent further development and troubleshooting – and

thus reliably delivers the highest possible quality. Over 40 vehicles are

permanently in use at the same time.

Key testing stages at a glance:

Development of engine, transmission, drive train, air conditioning system

Altitude testing in Denver, Colorado (USA), Lesotho (South Africa), Mont Ventoux

(France) and Granada (Spain)

High-temperature testing in Death Valley, California (USA), in Upington

(South Africa), Idiada test facility (Spain) and Phoenix, Arizona (USA)

Test drives in Los Angeles, California (USA)

Low-temperature testing in Arctic Falls and Arjeplog (Sweden)

Testing in the climate tunnel in Stuttgart

Development of cooling and fuel system

Various test drives on the high-speed circuits in Nardo (Italy), Laredo (Texas)

and Papenburg (Germany)

Testing in Upington (South Africa) and in Death Valley, California (USA)

Testing in the wind tunnel in Stuttgart

Development of brakes and control systems

Testing of the brake system on the high-speed circuit in Nardo (Italy) and

on the Großglockner Pass (Austria)

Testing of dynamic handling control systems at the Idiada test facility (Spain),

Arjeplog (Sweden) and Boxberg proving ground

At the same time, individual components such as the engine, drive train,

transmission, suspension and brakes, as well as the entire body structure are also

being tested to the limits on test rigs.

Accelerated endurance testing under gruelling conditions

Endurance testing complements the extensive vehicle development; it simulates

and compresses the entire (and particularly punishing) vehicle lifetime into a

short period. The aim is to ensure a high degree of maturity before vehicle

production starts in the Mercedes-Benz plant in Sindelfingen.

Endurance testing at a glance:

Endurance testing on a mixture of public roads:

Testing of interaction of all components and systems in everyday use. This test

phase calls for the vehicles to be loaded to the permissible gross vehicle weight

and to follow a precisely defined test programme comprising country roads,

motorways and urban roads

'Heide' endurance testing (named after the poor post-war roads across the

'Lüneburger Heide'):

Developers focus on the durability of the suspension components, the entire

body and the integral subframe to which the front axle, steering and engine are

attached. The test vehicles are loaded up to the permissible gross vehicle weight

Accelerated endurance test:

Whole vehicle testing focussing on drive train and suspension. Particular feature

of the AMG programme: 10,000 kilometres on the North Loop of the Nürburgring

and 10,000 kilometres on urban roads

Full-throttle endurance test:

Extreme acceleration and deceleration sequences with extensive full-throttle

operation; places high level of stress on cooling, fuel supply and braking systems

Global endurance test:

Whole vehicle testing focussing on drive train, suspension and body

Corrosion endurance test:

Corrosion testing on the entire vehicle simulates the toughest dynamic and climatic

conditions

Final board approval:

Overall review of development and production maturity

Around 30 Mercedes-Benz SLS AMG test vehicles will clock up some 1.25 million

test kilometres before development finishes in January 2010. The ultimate goal is

'final vehicle approval' – production of the first customer vehicles, the long

awaited 'job No. 1' can begin.