Press Release
Mercedes-Benz SLR McLaren
Comprehensive Overview for the US
Related content:
Mercedes-Benz SLR McLaren - Design Concept
Mercedes-Benz SLR McLaren - The Technology
Mercedes-Benz SLR McLaren Photo Album - 28 photos added/ 234 total
INTRODUCTION
The Mercedes-Benz SLR McLaren marks a new era of Mercedes-Benz passion for high-performance sports GT cars and, at the same time, celebrates the formidable SLR race cars of the 1950s. A futuristic interpretation of styling elements from the original 1955 Mercedes-Benz 300SLR roadster, the legendary SLR "Uhlenhaut Coupe" and the latest Formula 1 Silver Arrow race cars bridges the past and future, bringing cutting-edge motorsports-inspired design to the road.
Not only does the new SLR boast a rich heritage, but the new sports GT car also has an exciting future as a flagship within the multi-dimensional Mercedes-Benz brand. With by far the broadest product portfolio of any luxury automaker, Mercedes-Benz offers an array of models ranging from mid-size coupes to large premium sedans and wagons as well as sport utilities, luxury roadsters and now the limited-production SLR.
A Mercedes-Benz and McLaren Collaboration
The new SLR super sports GT car showcases the collective experience of Mercedes-Benz and its Formula 1 racing partner McLaren in the development and production of high-performance sports cars. This unique combination of expertise is evident not only in the impressive performance and pioneering developments of the new SLR, but also in its high levels of safety and practicality.
617-Horsepower V8 Powerplant
A front-mid-engine V8 producing 617 horsepower rockets the new SLR from zero to 60 miles per hour in under 3.8 seconds, and its top speed is over 207 mph. Stopping the car is equally quick, thanks to ceramic brake discs and an innovative air brake - an adaptive rear spoiler in the trunk lid. When the driver hits the brake pedal above 59 mph, the spoiler or wing pops up at a 65-degree angle, increasing air drag and providing greater down force.
AMG Supercharged Power
Each supercharged SLR engine is hand built at AMG's manufacturing facility in Affalterbach, Germany. The engine's dry-sump lubrication system (originally developed for race cars to prevent oil starvation during extremely hard cornering) includes a remote oil tank that eliminates any conventional oil pan or sump, allowing the engine to be mounted lower in the frame for better aerodynamics and an even lower center of gravity. The powerplant is also mounted in a front mid-engine position -- behind the front wheels.
Carbon Fiber Body
One dramatic example of technology transfer from Formula 1 racing is the carbon fiber composite construction of the SLR body, which provides rigidity and strength never before achieved in road-going vehicles. Equally impressive is its high level of occupant protection. In a serious collision, specially designed crash structures of carbon fiber help the new super sports GT car absorb over four times more crash energy than convention steel or aluminum.
Ceramic Brake Discs
The ceramic brake discs on the SLR are made of a new composite material - a carbon fiber-reinforced ceramic that boasts astounding stopping power, high heat resistance, outstanding structural strength and long service life. The high-performance SLR is one of very few production cars to make use of ceramic brake technology. Fitted with huge eight-piston calipers up front, the brake system alone can decelerate the SLR up to 1.3 g, and the air brake or adaptive rear spoiler adds to the brake force, especially at high speeds.
Reinventing the SLR Legend
The first SLR was one of the most successful sports racing cars of all times, and like the new car, the SLR of the 1950s combined leading-edge technology from the SL sports car and the Mercedes-Benz Formula 1 race car. Its three-liter, straight-eight engine made 310 horsepower, pushing the 300SLR to speeds of around 190 miles per hour.
The original SLR's most astonishing feat took place at the 1955 Mille Miglia -- at the time, a no-holds-barred race through Italy over twisty public roads. Setting a record never to be matched, Stirling Moss and Dennis Jenkinson piloted the 300SLR over the 1000-mile road course in 10 hours, seven minutes and 48 seconds!
The Uhlenhaut Coupe
Perhaps the purest roots of the new SLR can be traced back to the legendary Uhlenhaut Coupe. Head of both passenger and race car development at Mercedes-Benz in the 1950s, Rudolph Uhlenhaut built two street-car prototypes of the formidable race car, but the coupe versions never went into production. The 300SLR coupe - known to car enthusiasts as the "Uhlenhaut Coupe" - incorporated some of the design and technology from the 300SL Gullwing with the 300SLR roadster. Weighing less than 2500 pounds and boasting 310 horsepower, the Uhlenhaut Coupe had a top speed of about 180 miles per hour, making the two-seater the fastest car of its time to be registered for use on public roads.
SLR ENGINE
Prodigious power and high-tech features drawn from the racing world - these qualities define the first V8 developed exclusively by Mercedes-AMG. Their engineers meshed the high standards of the Mercedes-Benz brand with their 30 years of motorsports experience. The culmination of their initial analysis encompassing a wide range of engine designs, they settled on a 90-degree V8 displacing 5.5 liters and using a screw-type supercharger.
The bottom line is impressive - from a mere 1,500 rpm, the SLR powerplant delivers over 440 foot-pounds of torque, which builds to well over 500 ft.-lbs. at 2,000 rpm. Its maximum torque of 575 ft.-lbs. begins at 3,250 rpm and continues undiminished to 5,000 rpm! This muscular torque curve (or mesa!) plus agile throttle response and a peak output of 617 horsepower at 6500 rpm make it one of the most powerful production engines in a modern
street car.
First, Let's Squeeze the Intake Air
The SLR engine makes use of a mechanical supercharger - essentially an engine-driven air compressor - which pressurizes intake air for increased torque and horsepower. Unusually compact, the SLR supercharger unit is nestled between the two banks of the V8 powerplant and features two screw-type aluminum rotors that are Teflon-coated for low friction and high air pressurization. Driven by the crankshaft via a poly-V belt, the Lysholm-type supercharger rotors can spin up to 23,000 revs per minute, forcing air into the engine at a pressure of 13 pounds per square inch or 0.9 bar. This means the supercharger pushes about 40,000 pounds of air per hour into the engine, up to 30 percent more than other such systems!
Then We'll Cool It Off
Pressurizing the engine intake air makes it hot and reduces its density, so the super-charged air passes through two intercoolers - one for each cylinder bank -- on its way to the engine. The water-cooled intercoolers act as radiators to cool off the hot air and keep it dense, increasing the amount of oxygen and ensuring top power.
The intercoolers have their own dedicated water circuit, completely separate from the conventional cooling system for the engine block and heads. All in all, the power of the SLR requires an ample cooling system for the engine as well as good cooling for its supercharged intake air. As a result, the car incorporates generous air inlets (and outlets) and a strong 850-watt suction type fan.
High-IQ Engine Management
AMG engineers developed a smart engine management system that manages the operation of the supercharger based on engine speed and load. For example, when the car is coasting, the supercharger is not driven by the engine. However, as soon as the driver steps on the gas pedal, the system engages a special electro-magnetic clutch, and instantly the supercharger is spinning. Because the air is pressurized in a fraction of a second, even the most discerning driver doesn't notice the transition to supercharged power.
At light throttle or part load, when pressurized air isn't needed but the supercharger is still spinning, an air recirculation flap opens, routing pressurized air back to the un-pressurized side of the intake air circuit. This reduces the force required to turn the supercharger rotors and improves fuel economy.
A Bulletproof Bottom End
AMG engineers applied their extensive racing experience and expertise in designing high-performance engines to many details of the SLR powerplant. The entire engine block is cast aluminum, with cylinder walls made of NiCaSil. Each dynamically balanced crankshaft runs in five main bearings made of a durable long-life plastic. Forged connecting rods and pistons are sorted in carefully balanced sets for smooth high-speed operation, and dual oil-spray jets in the block help cool the back of each piston.
Dry Sump Makes A Low-Profile Engine
Conventional engines use a single oil pump that pulls lubricating oil out of a reservoir (or sump) in the bottom of the block and supplies it to all the bearings throughout the engine.
However, the SLR has an unusual dry-sump lubrication system, again based on experience gathered in the racing arena. The SLR system uses two oil pumps - a five-stage suction pump keeps the bottom of the engine block "dry" and a two-stage pressure pump to supply all the bearings. Between the two pumps is a ten-quart oil tank that serves as a reservoir.
Dry-sump systems were originally developed for racing to prevent the engine-killing oil starvation that can occur with conventional wet-sump systems when oil sloshes to one side of the block during hard cornering, acceleration or braking. Dry sump systems also increase horsepower noticeably by reducing the usual drag created when a crankshaft churns in thick oil.
Without the usual sump (or pan) hanging below the block, the dry-sump engine could be mounted lower in the SLR body. This important benefit of a dry-sump oil system means a lower center of gravity for better handling, not to mention a lower hood line for improved aerodynamics and high-speed stability.
Twin-Plug, Three-Valve Architecture
The SLR engine makes use of innovative cylinder-head architecture that features two spark plugs and three valves for each cylinder. The three-valve layout allows the largest possible valve size that will still leave room for two spark plugs. Two intake valves feed the fuel-air mixture to each combustion chamber, and combustion heat in each of the large, single exhaust valves is dissipated through sodium filled valve stems.
Each cylinder head houses a single, hollow camshaft driven by double roller chains and silent, rubber coated sprockets. Twin rocker shafts in each head hold low friction, roller tip aluminum rocker arms to actuate the valves, and housed in the end of each rocker arm is a small hydraulic lifter that ensures quiet, maintenance free valve operation.
Two Spark Plugs for a Cleaner Burn
Using a single exhaust valve in each combustion chamber makes room for two spark plugs per cylinder. Mercedes' innovative alternating, twin plug ignition system matched to the new three valve technology actually improves performance.
Among other things, the twin-spark system fires one plug after the other in quick succession and with varied "stagger," depending on engine load and speed. This shifting sequence (as well as the basic ignition timing) changes after each combustion cycle for extremely precise combustion control. This also enables close control of combustion chamber pressures to minimize noise without sacrificing efficiency. The twin-spark ignition allows an extremely lean air-fuel mixture and late ignition timing during warm up (retarded by 5 10 crank degrees compared to a single-plug design), to further increase exhaust gas volume and temperature.
Modular Camshafts Reduce Weight
AMG engineers designed special high-tension valve springs and light-weight modular camshafts. To make the modular cams, AMG starts with a precision seamless welded tube. Individually forged cam lobes are placed onto the tube. When all cam lobes are lined up, an expansion lance is pressed into the tube. The lance expands the tube hydraulically at each lobe position, fusing the lobes to the shaft. This modular process simplifies the design and manufacture of camshafts.
More Than Just Side Pipes
The SLR exhaust system features four catalytic converters - two on each side - and secondary air injection, which together ensure extremely low exhaust emissions. After the main converter housing, exhaust flows into a muffler located just behind each front wheel. The mufflers (each over five gallons in volume) are designed for low exhaust back pressure and consist of precisely calculated acoustic sections that produce the characteristic SLR engine sound.
The exhaust exits via a pair of 2½-inch stainless-steel pipes on each side of the car. Another reminder of the 1950s racer, the side pipes allow the underside of the car to be entirely smooth, which plays a crucially important role in the car's excellent aerodynamics and high-speed stability.
One Man, One Engine
Like all AMG engines, the SLR powerplant is assembled by hand in Affalterbach, Germany; it's then shipped to Woking, England for installation into the car. Each complete motor is the responsibility of one AMG engineer, who handles everything from bolting the crankshaft into the block to assembling the camshafts and installing the electrical wiring harness. Mercedes-AMG feels that the principle of "one man, one engine" is key to ensuring top-quality high-performance engines. Symbolic of this unusual commitment, every engine comes with a plaque mounted on the intake manifold that's signed by the engineer who assembled it.
Dual Fuel Tanks
The SLR engine draws its fuel from two low-slung, inter-connected fuel tanks - a layout that also contributes to the car's low center of gravity. The dual tanks are located on each side of the rear suspension and have a total volume of 25.8 gallons.
The tanks are equipped with two high-pressure electric fuel pumps that are controlled by the engine management system. To ensure that the fuel supply matches the needs of the engine, one pump runs all the time, while the second is activated only as needed, based on engine load and speed.
SLR TRANSMISSION
The Mercedes-Benz five-speed automatic transmission and rear final-drive unit, already used successfully in several high-performance models, have been further modified to handle the high torque of the SLR engine.
In addition to beefing up the gear housings and torque converter, gears in the center and rear planetary sets have been widened by five millimeters (about 0.2 inches), and the front planetary gears are two millimeters wider. While the wider gear teeth are stronger, this also makes room for larger bearings. What's more, the hydraulic clutches that drive and lock the planetary sets in each gear range operate at higher pressures.
The transmission oil cooler is larger than on other Mercedes-Benz high-performance models, and a separate oil cooler just for the rear differential/final drive unit is mounted under the trunk floor. Air flows through this cooler from a triangular NACA duct in the otherwise flat underside of the car and exits through a grill between the back-up lights.
A New Level of SpeedShift
The Mercedes-AMG Speedshift system offers even more features in the new SLR. A knob on the left side of the center console offers a choice of three settings: "Comfort," "Sport" or "Manual," and each setting is identified in the instrument cluster display by the letter "C," "S" or "M." While the two automatic shift programs are similar, "Sport" provides higher-rpm shift points and crisper shifts.
In the "Manual" setting, the driver can shift either with buttons on the steering wheel or by using the side-to-side Touchshift feature on the shift lever. Within the "Manual" setting, another knob on the right side of the console can select any one of three modes of progressively sportier shifting:
- Stage I - "Sport"
- Stage II - "SuperSport"
- Stage III - "Race"
In the sequence shown here, the shift response and transmission shifting speed become increasingly shorter.
SLR SUSPENSION
The SLR suspension features double forged-aluminum wishbones at all four corners. Its suspension design bears the signature of experienced race car developers and has been designed for excellence in three key areas: handling agility, active safety and comfort.
Negative Camber is Positive
Light unsprung weight is a distinct advantage, and in the case of the SLR, its aluminum suspension, stub axles and wheels as well as the super-lightweight ceramic brake discs all work together for extremely fast and sensitive handling response. Its relatively long wheelbase (106.3 inches), wide track (64.5 inches) and low center of gravity also contribute to the car's exemplary handling, especially when cornering at speed.
As the suspension compresses when cornering at high speed, the SLR wishbone geometry provides the wheels with slight negative camber for the best possible tread contact. At the same time, the rear suspension is designed with anti-squat characteristics on acceleration, and the front suspension layout minimizes dive during hard braking.
Formula 1 Stabilizer Bar
The front stabilizer bar is above the front suspension and is connected to the suspension by rocker-arm linkage - as in Formula 1 race cars. This layout means that the stabilizer bar does not break up the car's smooth underbody, which is vitally important for its outstanding aerodynamics and high-speed stability.
SLR STEERING
Fast-ratio rack-and-pinion steering with speed-sensitive power assist makes for precise, lightening-quick reflexes. Located in front of the engine, the lightweight steering gear unit has a ratio of 12.6, which gives drivers the impression that the car goes wherever the 15-inch steering wheel is pointed! The wheel is electrically adjustable for reach (2 ½ inches) and tilt (2.7 degrees).
SLR BRAKES
The high-performance SLR is one of very few production cars to make use of ceramic brake technology, a result of DaimlerChrysler materials research and Mercedes-AMG experience with high-tech brakes on the street and track.
Carbon-Fiber Ceramic Brake Discs
The brake discs on the SLR are made of a new composite material - a fiber-reinforced ceramic that boasts astounding stopping power, high heat resistance, outstanding structural strength and long service life. Carbon fiber, powdered carbon and resin are pressed into shape at high pressure during manufacturing and baked with a silicon compound at around 2700° Farenheit to form the ceramic. The benefits of ceramic brake discs are impressive:
The discs are temperature-resistant up to 1800°, which means high-speed fade resistance never before achieved in a production car.
Although they're over 14 inches in diameter, the SLR discs are less than half the weight of conventional steel discs - 14 pounds instead of 34.
The brakes can decelerate the SLR up to 1.3 g. The braking system's theoretical strength is 2000 horsepower!
For most owners, the SLR ceramic brake discs will last the life of the car.
Brake calipers on the SLR are specially designed to take advantage of the ceramic discs. Eight-piston fixed calipers are used on each front wheel and four-piston on the rear. Total brake pad area at the front end alone is 68.2 square inches, which contributes to outstanding braking. For example, the stopping distance from 62 mph is only 114 feet.
An Air Brake Helps Slow Things Down
An adaptive rear spoiler built into the trunk lid adds to the outstanding braking of the SLR. If the driver hits the brake pedal hard enough, the spoiler automatically flips up at a
65-degree angle, producing more than 300 pounds of extra downforce to make the brakes even more effective. At about 60 mph, the spoiler automatically rises to 10 degrees, and the driver can control the airbrake via a switch on the console up to an angle of 30 degrees.
SLR WHEELS AND TIRES
On U.S. models, "staggered" 19-inch turbine-style alloy wheels and tires are standard equipment, while 18-inch wheels are a no-cost/no-credit option for customers who prefer a different look (a choice of two styles -- five-spoke and ten-spoke) or a taller tire sidewall:
The first two dimensions -- tire width and sidewall height - are listed in millimeters, while the remaining dimensions are shown in inches. This industry convention includes expressing sidewall height as a percentage of the width. For example, the standard front tire is 255 mm wide (around 10 inches), and its sidewall height is 35 percent of that -- about 3 ½ inches.
Mercedes-Benz SLR McLaren
Comprehensive Overview for the US
Tire Pressure Monitoring
The SLR comes with a tire monitoring system that has pressure sensors built into the inside end of each tire valve. As the wheels spin, the information is transmitted by radio to antennas inside each wheel well. The signals are processed by a central control unit that can distinguish the signals from each wheel, and information on each wheel is shown on a central display in the cockpit.
ESP STABILITY CONTROL
ESP electronic stability control and SBC electronic braking are integral parts of the SLR’s safety and dynamic handling systems. Since the electronic braking system uses a high-pressure accumulator to hold brake fluid at a pressure of 2000 to 2300 pounds per square inch, this power means that the ESP system works even better than on ESP-equipped models with conventional brakes. Thanks to even faster and more finely metered brake impulses from the high-pressure accumulator, ESP can stabilize a skidding vehicle at an earlier stage.
Engineers developing the SLR thought it might be a challenge to adapt the stability control system to the car’s distinctly sporty performance while maintaining their usual safety standards. However, with its sophisticated sensors and light-speed reactions combined with sheer braking power, the presence of the electronic braking system actually made it easier to fine-tune ESP for a very sporty driving style that allows moderate oversteer and understeer when driving the SLR, but without compromising active safety.
Mercedes-Benz invented ESP stability control in the 1990s and debuted the system on its more expensive 1996 models in the U.S. The high-tech feature is now standard equipment on all models.
ESP Works Like a Mind Reader
ESP calculates every microsecond if the car is going exactly in the direction it is being steered. If there’s an appreciable difference between what the driver is “asking�-- through the steering wheel -- and what the vehicle is doing, the system corrects with split-second speed by applying one of the left or right-side brakes, even before the driver may sense any changes.
ESP uses steering wheel angle and wheel speed to calculate the path being steered, and it gets signals about lateral “g� forces and “yaw� to measure what the car is actually doing. (Imagine turning a model car on a toothpick stuck down through the roof – that’s yaw!)
Whenever it senses understeer, ESP increases brake pressure to the inside rear wheel. With an oversteer tendency, it increases brake pressure to the outside front wheel. Unlike traction control, ESP is effective during acceleration, braking and coasting. The system enhances driver control and helps maintain directional stability in turns as well as when driving straight-ahead, including on uneven surfaces and over patchy snow, ice or gravel.
ELECTRONIC BRAKING
In the SBC electronic brake system -- another Mercedes-Benz invention -- light-speed electronics replace many of the mechanical and some of the hydraulic parts. A powerful micro-computer oversees the system’s operation by processing information from a series of sensors and control units.
The pedal is no longer connected hydraulically to the wheels (except for a backup system that operates the front wheels conventionally in the unlikely event of an electronics problem). The brake pedal and master cylinder are merged into a single operating module (a conventional vacuum-powered brake booster isn’t needed), and this module primarily transmits brake commands to the microcomputer via electronic impulses.
The Nerve Center – Electronic and Hydraulics Working Together
The centerpiece of the electronic braking system brings together the microcomputer, wheel pressure modulators, a hydraulic pressure reservoir and an electrically-driven hydraulic pump. The operation of this assembly highlights the interdisciplinary beauty of the system – while hydraulics still provide the sheer braking power, electronics make it work faster and better than ever:
- The electronic braking microcomputer calculates exactly the right brake force for each wheel by processing signals from the pedal unit and from sensors all over the car. It considers wheel speed data from the ABS system, steering angle and cornering g-forces from the ESP system, as well as signals about the engine braking effect and which gear is engaged from the engine-transmission microcomputers.
The result of these complex calculations is instantaneous brake commands, which means maximum braking and driving stability.
- The high-pressure reservoir holds the hydraulic oil or brake fluid that powers the system under 2000-2300 pounds per square inch of pressure. The microcomputer controls an electric pump and regulates hydraulic pressure throughout the system. The overall result is much shorter response times compared to conventional brake systems. This system also provides full braking power even when the engine is off.
- Four wheel pressure modulators regulate brake pressure at each wheel based on everything processed by the microcomputer. Each wheel is braked individually to ensure the greatest possible driving stability and optimal deceleration. A pressure sensor for each wheel modulator, for the reservoir and for the pedal unit help the microprocessor to monitor everything.
Braking Around Corners Like Never Before
If braking is ever necessary in a turn, conventional systems apply the same brake pressure on the inside and outside wheels. However, the SBC electronic brake system increases pressure to the outside wheels and reduces it on the inside ones. This takes advantage of the vehicle’s natural weight transfer during cornering and increases vehicle stability, in part by reducing the tendency to lock the inside wheels when braking in turns. To provide this valuable left-right brake proportioning, the microcomputer processes signals from the ESP steering angle sensor and lateral G-force sensor.
In a similar way, front-rear brake proportioning is also part of the system’s built-in algorithm. To prevent dangerous over-braking on the rear wheels, the majority of the braking force is placed on the front wheels during high-speed braking. At low speeds and when braking lightly, the system places more of the braking pressure on the rear wheels, ensuring smoother response and more equal wear on the brake pads.
Built-in Brake Assist for Faster Emergency Braking
Among the greatest benefits of the Mercedes-Benz electronic braking system is the ability to respond to driver and vehicle behavior as well as make use of the extremely fast buildup of brake pressure.
If drivers switch their foot quickly from the accelerator to the brake pedal, the electronic brake system recognizes the early signs of an emergency situation and reacts accordingly. First, the microcomputer “primes� the system by raising brake pressure in the connectors and pressing the brake pads lightly against the disks.
As soon as the brake pedal is pressed, full-power braking is applied with the help of the high-pressure reservoir. In practical terms, this means that alerting the system and then applying full pressure shortens the stopping distance from about 80 mph by some three percent!
A Comfortable Pedal
To simulate the familiar pedal feel of conventional brakes, Mercedes engineers utilize the tandem hydraulic cylinder that operates the front brakes only in the event of an electronic failure. In normal operation, this master cylinder is hydraulically “decoupled� from the rest of the system.
Staying Dry in the Rain
Wet brake discs can mean an instant of terror until the wheels make one turn and the brake pads squeegee a film of water from the disks. In wet weather, the electronic brake system provides short, imperceptible brake impulses to wipe off the water, ensuring fast brake response. This automatic drying feature works whenever the windshield wipers are on.
SLR BODY
The body of the Mercedes-Benz SLR McLaren is as high-tech as the rest of the car. Most of the car is made of carbon fiber composite – the entire body shell, its gull-wing doors, the hood and underbody structures at the front and rear. Overall, the SLR is about 30 percent lighter than a comparable vehicle with conventional steel construction.
While this extremely strong yet lightweight material originated in the aircraft and aerospace industries, carbon fiber has proven itself dramatically on the world’s top race tracks. As Formula 1 developers have begun used carbon fiber crash structures over the past several years, the F1 racing discipline has seen a dramatic reduction in serious injuries from collisions.
Half the Weight and Four Times the Energy Absorption
Carbon fiber is half the weight of comparable steel parts and 30 percent lighter than aluminum! What’s more, carbon fiber absorbs four to five times more energy than steel or aluminum in a collision.
Mercedes-Benz takes advantage of this extraordinary energy absorption by installing a two-foot longitudinal member made of specially designed carbon fiber on each side of the SLR front end. In a head-on collision, the fibers in these conical crash members shred from front to rear with absolutely consistent deformation, ensuring steady deceleration. With their ever-changing cross-section, the conical carbon-fiber crash members not only have predictable energy absorption but also a weight advantage, since the design uses only as much material as is actually needed. Each of the longitudinal members weighs only 7 ½ pounds.
The First Production Car with Carbon-Fiber Crash Structure
The carbon-fiber crash members are bolted to an aluminum sub-frame for the engine, and at the front, they connect to the body shell by means of a cross member and a flat sandwich panel, both made of carbon fiber composite. As a result, the SLR is the world’s first production car with a front crash structure made entirely of carbon fiber. At the rear of the car, similar carbon-fiber crash members, along with a hefty cross member, handle energy absorption in the event of a rear impact.
Four Years of Careful Development Work
The goal of engineers from the Advanced Design department at the Mercedes-Benz Technology Center and from DaimlerChrysler Research was not only to design crash members with unprecedented passive safety, high strength and low weight, but also to develop the first automated manufacturing processes for carbon fiber. Prior to the SLR project, carbon fiber parts for race cars and airplanes alike have been made by hand – an extremely time-consuming process.
Early steps included the first-ever development of a special algorithm for calculating crash dynamics on carbon fiber. Sophisticated computer simulations were crucially important to fine-tuning the crash structure. At the same time, materials experts were testing the calculations by conducting precise drop-tests of carbon fiber models. Over a four-year period, design details of the SLR crash members were gradually defined.
The First-Ever Automated Production of Carbon Fiber
To transform the world of carbon fiber from slow hand work to automated production, Mercedes-Benz materials experts took a careful look at the textile industry. They ultimately took conventional production methods of sewing, knitting, weaving and braiding fabrics and adapted them for making high-performance carbon fiber.
For example, the web of the SLR’s front crash members is formed by laying several layers of carbon fiber on top of each other and sewing them together by machine. Then the piece is cut into shape, folded into a double-T profile and inserted in a plastic braiding core, which in turn is clamped into a special braiding machine. Each crash member is braided together with 25,000 extremely fine carbon filaments that are simultaneously unwound from 48 reels. This technology allows carbon fiber to be braided around the core at specific angles to create the right contour, and several layers are even laid on top of each other in certain areas to get the right thickness.
A computer-controlled tufting machine then joins the inner web to the braid of the longitudinal member, after which the plastic core is removed. Then the pre-formed crash member is trimmed to the correct size and injected with resin.
Several patented processes were developed to ensure good repeatability and short cycle time – critical factors for series production. Making the complex carbon-fiber structure of the SLR’s front crash members takes just 12 minutes, a clear demonstration of the potential offered by this innovative manufacturing technology.
SLR Uses Advanced Sheet Molding Compound Method
The rear shelf of the new SLR provides another example of new techniques used by Mercedes-Benz for producing carbon fiber components. Although it’s a complex shape with several openings, the rear shelf is manufactured in one piece using a new Advanced Sheet Molding Compound method.
A machine automatically positions several layers of carbon fiber composite in the basic shape, and under heat, this blank is pressed into the exact shape of the rear shelf. No further steps are needed. Mercedes-Benz is the first automaker to use components made by the Advanced SMC method.
McLaren Composites
The McLaren Composites company also manufactures more than 50 carbon fiber and fiberglass parts for the new high-performance sports GT car. The entire floor assembly, including all support members and securing points, is made in one piece, as is the roof frame, which is filled with foam before the resin is injected to create an especially crashworthy sandwich structure. High-strength bonding and riveting techniques connect the sections of the chassis and body shell.
An aluminum sub-frame for the engine mounts is bolted to a carbon fiber bulkhead and bonded in place as well. In the rear, steel mounts are bonded into the carbon fiber for the rear differential/final drive unit.
PASSIVE SAFETY
A cutting edge restraint system with six airbags, seat belt tensioners and belt force limiters completes the safety picture on the SLR. In a frontal collision, the system first triggers the seat belt tensioners, which pull taut up to six inches of loose belt, limiting occupants’ forward motion. The belt tensioners are also activated if the car senses a rollover.
Smart Front Airbags Feature Two-Stage Deployment
In a more severe collision, two-stage front airbags also deploy. Two sophisticated sensors just behind the front bumper (on the radiator cross member) and one right in the passenger compartment (on the transmission tunnel) measure the severity of the impact, and an electronic control unit decides with lightning speed whether one or both chambers of the two-stage gas generators are triggered.
In a high-force collision, both stages are deployed, inflating the front airbags more quickly. The driver’s airbag has a volume of 2.26 cubic feet when inflated, while the passenger’s front air bag is 4.41 cubic feet. The passenger air bag is larger because of a wider possible range of occupant positions.
Knee Bags Help Out
At the same time as the front air bags, two knee bags deploy from the underside of the SLR dash, supplementing the protection provided by the seat belts and front airbags as well as reducing the natural tendency for occupants to “submarine� under the seatbelts.
Belt Force Limiters Fine-Tune the Protection
An instant after the belt tensioners have tightened the seat belts and the airbags have deployed, belt force limiters allow the belts to loosen slightly, to take full advantage of the fully inflated airbags’ cushioning effect and minimize the risk of chest or shoulder injuries from the belts.
Side Airbags for the Head, Neck and More
In a side impact, an airbag deploys from the door, ripping open a seam above the armrest and inflating in milliseconds. Sometimes referred to as a “head-thorax bag,� the SLR door-mounted side airbag is oblong when deployed so that it covers most of the side window. This design provides crucially important protection to the head and neck, not to mention shielding occupants from glass shards and other intruding objects in a collision.
Complete with Baby Smart
The passenger’s front airbag can be turned off by the standard-equipment BabySmart system if it senses the presence of a BabySmart-compatible child seat. Available in several sizes, BabySmart seats feature a built-in transponder that communicates with sensors in the seat upholstery. Without anyone having to operate a switch or connect any wires, the system automatically deactivates the large front airbag on the passenger side whenever the BabySmart seat is installed in the car. However, the seat belt tensioner and sidebag remain active, providing valuable protection to a young passenger in an accident.
SLR DESIGN
From first glance, the Mercedes-Benz SLR McLaren speaks the dramatic design language of today’s Formula One race cars blended with an echo of classic styling elements. The bold look of the Silver Arrow race cars that took the Mercedes McLaren team to Formula One World Championship glory is apparent in the stunning road car, and when the gullwing doors of the new SLR swing open, its historic connection to the 1955 Uhlenhaut coupe becomes even more obvious.
Gullwing Doors with an Avant-Garde Look
In their modern interpretation, the SLR’s gullwing doors swing up and forward from the front roof post – the “A� pillar – instead of directly from the roof as with the Mercedes-Benz gullwings of the 1950s. The new doors open at a 107-degree angle, providing a safer, larger door opening (for easier access to the interior) and creating an exciting, futuristic look.
Powerful Proportions Connect the Future and Past
The overall look of the new SLR features powerful proportions that start from a long, broad front hood, transition into a compact passenger cell and finish with a short trunk section. The centerpiece of the front hood is an arrow-shaped nose that’s reminiscent of the Mercedes McLaren Formula One race cars that won World Championships in 1998 and 1999.
An F1 Nose with a Twin-Fin Spoiler
Another distinctive F1 element can be found under the arrow-shaped nose – a twin-fin front spoiler that’s more than decoration. The fins create aerodynamic downforce that contributes to the car’s sure-footed, race-car-like handling. The fin motif is a recurring theme that helps create design consistency across the exterior of the SLR. Finned sections connect the headlights to the nose, support the side mirrors and adorn the wrap-around taillights, where 51 LEDs on each side are housed in two fins, one above the other. The LEDs are brighter, last much longer and light up faster – about 150 milliseconds before conventional bulbs.
A Familiar Face Gets A Fresh Look
Above a large intake for engine cooling air, four elliptical headlights are arranged in a fresh treatment of the familiar face that has identified Mercedes-Benz cars for nearly a decade. On each side, two ovals form single units that house powerful xenon projection lights under clear covers that resemble high-quality camera lenses.
The headlights form a strong starting point for the lines of the hood and front fenders. The contours of the lights develop into sculpted curves along the hood that deliberately evoke images of an athlete’s sinewy muscles. These taut lines sweep back to the A-pillars, visually connecting the nose of the car to the passenger compartment.
A Strong Profile, Too
From the side, the eye is caught by the SLR’s flat, wedge-shaped profile. This shape is created by the long front hood, a steeply raked front windshield and short trunk section, which together emphasize the sense of forward tension throughout the new SLR supercar.
Just behind the front wheels, finned “gills� do much more than recall the design of Mercedes-Benz sports cars and racers from the 1950s. These stylized openings serve as vents for the all-important cooling air that exits the engine compartment, and under the gills, side pipes from the engine exit as well. The lines of the gills are accented by tapered fins that sweep back into the surface of the gullwing doors.
The SLR Interior Rocks
Inside the car, an obvious focal point is the center console, which is a visual extension of Formula One domes on the front hood. The console also picks up the lines of the front end as they flow over the transmission tunnel toward the back of the car. The upper console is dominated by the two knobs for transmission shifting modes, and a no-nonsense hand brake is nestled between the console and the passenger seat.
A Cocoon of Aluminum, Leather and Carbon Fiber
An interplay of materials creates a tasteful ambiance. Aluminum and carbon fiber contrast with supple leather that’s available in four color choices: Black, Orion Grey, Berry Red and the classic 300SL Red – the one color that uses extra soft “Silver Arrow� leather. The seats feature four different sizes of removable side bolsters that allow the one-piece buckets to be tailor-fitted.
A 15-inch three-spoke steering wheel comes with rocker switches to operate the multi-function display as well as push buttons for manual gear shifting. Looking through the wheel, cleanly styled chronometer gauges are positioned squarely in front of the driver. An 8000-rpm tachometer shares center stage with a 220-mph speedometer, and they’re flanked by the requisite engine temperature and fuel gauges.
And A High-Performance Trunk
The trunk of this high-performance sports GT car is surprisingly roomy, with 9.6 cubic feet of luggage space finished in leather and velour. Lift-up flaps provide easy access to compart-ments for the two batteries, windshield washer and brake fluid reservoirs, and the tool kit. This layout helps ensure even front-rear weight distribution and a low center of gravity.
IN CONCLUSION
Combining unmatched supercar performance with surprising luxury and comfort, the SLR is destined to be a formidable competitor with revered brands from the other side of the Alps as well as the other side of Stuttgart. Unlike most of its direct competition, the SLR is equally at home on the way to the corner store, in city traffic, on twisty back roads and blazing down a race track at over 200 miles per hour.
As a result, the Mercedes-Benz SLR McLaren is changing the way people think about supercars. And, never before has there been such collaboration among a World Champion Formula One race team, a renowned boutique for high-performance cars and a global luxury car brand. McLaren, AMG and Mercedes-Benz are on their way to reshaping the world of exotic and super sports GT cars.
Mercedes-Benz SLR McLaren
Comprehensive Overview for the US
Interior
Harmony of forms and materials
- Motor racing character with new dimensions in comfort
- Exciting cockpit design focuses on the essentials
- Top-class automatic climate control with sophisticated sensor system
- Top-quality radio, sound system and navigation system
The combination of luxurious appointments and a stark sports car-style feel creates a uniquely spellbinding atmosphere on board the Mercedes-Benz SLR McLaren. Exclusive, soft "Silver Arrow" leather, specially developed for the SLR, and select materials such as alumin-ium and carbon contrast strikingly with the pure functionality of a vehicle whose roots lie in the world of motor racing. In the interior, as in the exterior, the motor racing heritage is combined with the clear advantages of a classic Gran Turismo: outstanding ride comfort and a deliber-ate concentration on the pleasures of refined dynamic driving.
Despite its focus on luxury and comfort, the Mercedes-Benz SLR McLaren's interior dimen-sions are clearly those of a high-performance sports car. In keeping with extraordinarily high demands in terms of dynamic handling, the passenger cell is compact, creating a tailored feel. Nevertheless, there is a generous sense of space inside the two-seater, thanks, in part, to the deep seat position, which allows a low roof line, at the same time lowering the centre of grav-ity, which benefits dynamic handling. The backrest of the carbon fibre seat is set at an angle of 28 degrees to the seat cushion, rather than 25 degrees, in order to allow a sporty seating position.
Generous dimensions ensure an attractive interior. The SLR exceeds the shoulder and elbow width dimensions of many luxury and mid-class saloons, providing its occupants with plenty of personal space. The key interior dimensions of the Mercedes-Benz SLR McLaren:
Interchangeable seat cushions for an individual fit
Having entered through the wide-opening swing-wing doors, the driver and passenger take their places on light, single-piece carbon fibre seats, the basic design features of which have proven their benefits in the world of motor racing. Thanks to the multi-layer carbon fibre com-posite structure, they are not only 25 percent lighter than conventional car seats but also offer ergonomic advantages: a set of two upholstery modules, in three different sizes, allows the seat contour to be adapted individually to the anatomy of the driver. Three sets of these side upholstery modules are available, ensuring that the seats can be adapted to the optimum up-per body and hip width for the driver, providing made-to-measure lateral support. The individ-ual modules, upholstered in semi-aniline leather, are bolted onto the carbon frame.
The single-piece carbon fibre composite frame is connected at four points to an electric seat adjustment mechanism, which is used to adjust the seat's fore-and-aft position (by 130 millimetres), height (by 41 millimetres) and angle (up to 9.6 degrees) according to per-sonal requirements. As a result of the single-piece design of the carbon fibre composite seat frame, the angle of both the seat cushion and the backrest are adjusted simultaneously.
High-class chronometer look for cockpit
Even the process of inserting the electronic ignition key has been imbued with an enthralling, uniquely SLR feel: a starter button on the solid metal shift knob at the top of the gearshift lever on the centre tunnel instantly begins to glow red. Apply slight pressure with your thumb, and the grid-style flap opens to provide access to the illuminated button. One press with your thumb brings the tremendous power of the V8 supercharged engine to life.
The interaction of various well-designed details in the interior underlines the thoroughbred character of the SLR at all times. Nevertheless, the cockpit design deliberately focuses on the essentials, in keeping with motor racing philosophy. Easily readable characters on a dark background, which were specially created for the SLR, define the instruments' attractive, classic chronometer design – a design which, even at first glance, signals outstanding preci-sion. They are enclosed by a matt chrome surface and are flanked by further displays, indicat-ing the coolant temperature (left) and tank capacity (right), plus pilot lights and warning lights which only light up when the ignition is started or if there is a fault.
The brightness of the backlit dials automatically adapts to the prevailing light conditions in the interior of the swing-wing-door vehicle. A further unusual detail: when the engine is started, the needles spring back to their home position.
Cutting-edge displays in the lower section of the speedometer and the rev counter serve as an information centre for a number of functions. The aim of this control and display concept is to inform the driver of the operating status of the car without diverting his or her attention from the road. The two central displays are coupled both with the multifunction steering wheel and with the car radio, the telephone and the navigation system – which means that, at the touch of a button, the driver's personal list of stations, the selected CD, the telephone directory or navigation information appears directly in the driver's field of vision.
Multifunction steering wheel with buttons for quick gear changes
Eight illuminated buttons on the multifunction steering wheel allow the driver to specify his or her requirements – a light tap with the thumb is all it takes. They provide a simple means of regulating the volume and of accepting or terminating phone calls.
The three-spoke steering wheel, which has a diameter of 380 millimetres, was specially de-signed for the Mercedes-Benz SLR McLaren. It can be adjusted for reach by 60 millimetres and its height can be varied by 2.7 degrees. On the back of the spokes are buttons which the driver can use to change gears in Manual mode without having to take his or her hands from the wheel – a familiar feature in Formula 1.
Aluminium console with buttons for airbrake and shift program
The centre console, made from high-grade aluminium, is a further eye-catching feature on board the high-performance sports car. It houses not only the car radio with its navigation sys-tem, but the climate control unit and several new switches too, which activate and control various innovative technological features on board the SLR.
One of these switches operates the airbrake on the boot lid. From a speed of 95 km/h this automatically extends to provide more downforce, and when slowing down it rises to a steep angle to ensure optimum deceleration. The SLR driver can also use the switch here to posi-tion the airbrake as required.
The two rotary switches on the centre console are a further unusual feature. They can be used by the driver to select between the automatic transmission's three different shift pro-grams: "Manual", "Comfort" and "Sport". The driver can also use the right-hand rotary switch to determine the speed of the gearshifts.
The radio and navigation unit are also accommodated in the centre console,
concealed by an aluminium flap so as not to distract the driver. Beneath the
radio/navigation unit are two ergonomically placed aluminium rotary switches for controlling the air conditioning system.
Material concept underlines elegance and sportiness
In the two-tone interior, which uses only select materials such as high-quality leather, fine Al-cantara for the entire roof trim and elegant pearl velour for the carpets, the dashboard is dark in order to prevent irritating reflections while the seats, door panels, tunnel trim, rear wall con-sole and the rear shelf panel come in a contrasting colour.
There are plenty of inspired details: the high-quality integral loudspeakers in the door panels, for example, have a grid-form cover which echoes the styling of the air outlets on the sides of the vehicle. The rear of the grid surround forms the door handle, while a simple leather loop in the upper area of the door serves as a separate door pull – a traditional feature derived from the legendary Mercedes-Benz motor racing vehicles. The uncompromising, clean-cut interior of the Mercedes-Benz SLR McLaren also features aluminium pedals with rubber studs.
Large boot and roomy stowage compartments
An exceptionally large, saloon-style boot underlines the fact that this is a thoroughbred Gran Turismo, designed for long-distance travel. According to the VDA measuring method, it has a capacity of 272 litres. Even when the luggage compartment is fully laden, the occupants are still assured unimpeded access to the CD changer, which is housed in the boot.
In addition to the spacious boot, there is plenty of stowage space in the interior – a total of 46.1 litres, including a 42.5-litre compartment below the rear shelf. Further stowage com-partments can be found in the rear wall and console of the centre tunnel.
The switches for adjusting the seats, the power window buttons and the door release are po-sitioned within easy reach between the door sill and the seat, providing a further example of the sports car's consistent use of space and ergonomic design. The handbrake is located in a moulded recess to the right of the centre tunnel.
Automatic climate control with sensors which register the position of the sun, the air quality and humidity
Despite its uncompromising motor-racing character, the Mercedes-Benz SLR McLaren is fit-ted with a state-of-the-art climate control system, which offers the ultimate in power, function-ality and controllability. The two easy-grip aluminium dials on the air conditioning control unit in the centre console allow separate temperatures to be selected for the driver and passenger side – the set value is illuminated on the aluminium dial.
In automatic mode, a microcomputer monitors the functions of the automatic climate control system, receiving and processing a whole range of data. This includes information on the bat-tery voltage, coolant temperature, engine speed and road speed plus the position of the doors and the side windows. Sensors supply further key readings:
- Two sensors continuously record the temperature in the interior.
- A solar sensor on the dashboard measures the angle of incidence and intensity of the sun's rays so that the temperature, quantity and distribution of the air blown into the interior can be regulated appropriately.
- A dew point sensor in the air conditioning system's intake duct registers humidity and al-lows economic regulation of the refrigerant compressor.
- A pollutant sensor in the automatic climate control system's intake channel detects any in-crease in the concentration of carbon monoxide and nitrous oxides in the incoming air. If an increase is detected, the system automatically switches to recirculation mode.
Like the automatic climate control system in the SL-Class sports car, the system on board the SLR operates according to the reheat principle: depending on its humidity, the incoming air is first cooled and in the process dried so as to ensure mist-free windows. Only then is it passed through the heating element and heated to the desired temperature.
Sophisticated lighting concept for the interior
One of the air conditioning system's sensors, which records the interior temperature, is ac-commodated in the overhead control panel. The panel also houses the switches for several of the lights which make up the sophisticated interior lighting concept.
Special features include lights below the sun visors which automatically switch on as soon as the visor is folded down and the vanity mirror opened. There is also a reading light which is installed in the interior mirror, and the doors each feature a round lens-shaped light which il-luminates the door sill area when the doors are opened. The intensity of most of these lights is automatically regulated according to the ambient light conditions.
Specially adapted audio and navigation system
The Mercedes-Benz SLR McLaren is equipped with a top-class communication system which has been adapted to the requirements of a high-performance sports car. The Audio 30 APS car radio combines a radio and a cassette player plus the controls for the CD changer and the dynamic-route-guidance navigation system in a single unit. It has a clear design, is easy to operate and its functions are displayed in the speedometer and the rev counter – which means that the driver can concentrate on the driving rather than searching for information in excessive detailed displays.
The optimum sound quality comes courtesy of the Bose sound system, which has been spe-cially attuned to the SLR. It uses a total of seven loudspeakers and sophisticated electronics, and not only compensates for interference but also has a microphone which constantly regis-ters driving noise and adjusts the volume accordingly, without the driver having to intervene.
Other integral features include the permanently installed mobile phone system and all of the aerials which are required for radio and telephone reception and for operating the satellite navigation system.
Telematic functions for accidents or breakdowns
SLR drivers also benefit from new traffic services with this cutting-edge communication sys-tem. The following highly effective telematic functions are available:
- TELEAID is an automatic emergency call system which, in the event of an acci-dent, sends out an SOS signal to alert the emergency services and lead them to the scene of the accident. The emergency call is either triggered via a crash sensor or by pressing a button in the overhead control panel. At present TELEAID functions in Germany and the USA.
- TELEDIAGNOSIS makes contact with Mercedes-Benz's central Customer Assis-tance Centre (CAC) at the touch of a button on the car phone headset, at the same time in-forming the centre of all necessary vehicle data and the precise position of the car. This means that service personnel can be directed to the vehicle quickly and precisely. TELEDIAGNOSIS is available in Germany.
- MB Info is a service which offers Mercedes customers the opportunity, using the TELEAID technology, to direct general questions to the customer advisors at the Customer Assistance Centre. One touch of the "Info" button is all it takes to establish a free call. This service is currently offered in Germany and will be extended to other countries in the future.
Mercedes-Benz SLR McLaren
Comprehensive Overview for the US
Standard Options
The new SLR is also being launched with a number of other top-class technical features designed to raise safety and comfort to the highest level – ranging from the new kneebags and the powerful bi-xenon headlamps to the sophisticated sound system with its dynamic navigation facility. A selection of the long list of top-quality standard equipment features is provided below:
- Stowage compartments in centre console, between seats at rear and below rear shelf
- Adaptive airbags
- Aero windscreen wipers
- ASSYST PLUS active service system
- Aerial for car phone
- Anti-lock braking system (ABS)
- Outside temperature display
- Courtesy lights in doors
- Automatic tyre pressure monitoring
- "Audio 30 APS" car radio with CD changer and dynamic navigation system
- Car phone
- Bi-xenon headlamps
- Floor mats with SLR logo
- Brake Assist
- Electrically adjustable, single-piece carbon-frame seats, in three different sizes with interchangeable upholstery modules
- Anti-theft alarm system
- Electronic Stability Program (ESP®)
- Headlamp Assist
- Power windows
5-speed automatic transmission with three programs and choice of manual shift speeds
- Belt tensioners and belt force limiters
- Head/thorax sidebags in doors
- Interior lighting with night design
- Automatic child seat recognition
- Automatic climate control
- Kneebags
- Leather upholstery and leather interior appointments
- Light-alloy wheels
- Steering column, electrically adjustable
- Multifunction steering wheel with buttons for manual transmission control
- Fog lamps
- Rain sensor
- Trip computer
- Heated windscreen washer system
- Headlamp cleaning system
- ELCODE locking system
- Sensotronic Brake Control (SBCTM)
- Sound system
- TELEAID, TELEDIAGNOSIS and MB Info telematic services
- Cruise control with SPEEDTRONIC
- Touchshift
- TIREFIT with electric pump
- Central displays in instrument cluster
- Central locking with remote control
Mercedes-Benz SLR McLaren
Comprehensive Overview for the US
Technnical Specifications