Tuesday, June 20, 2006

Chevrolet Corvette C6R





In Detail
engine      V8
position   Front Longitudinal
drive wheels RWD


France - Corvette and Aston Martin went toe-to-toe in the 24 Hours of Le Mans, trading blows through a grueling day and night of racing. When the battle finally ended at 5 p.m. today, Corvette Racing had won the GT1 class in the world's greatest sports car race for the fifth time in six years.

The victorious No. 64 Compuware Corvette C6.R driven by Oliver Gavin, Olivier Beretta and Jan Magnussen finished fourth overall. It was the trio's third consecutive class victory at Le Mans and their fourth straight endurance racing win, a streak that includes last year's 24 Hours of Le Mans, Petit Le Mans and the 12 Hours of Sebring. Corvette Racing extended its perfect finishing record in the 24 Hours of Le Mans to seven consecutive years and Corvette became the winningest manufacturer in recent GT history at Le Mans.

This year's 24-hour endurance test reprised the drama of last year's battle. The No. 63 Corvette C6.R and the No. 009 Aston Martin DBR9 were in lockstep from the start, separated by less than a lap in the running order for hour after hour. The turning point came in the 22nd hour when the green Aston Martin went to the garage with a mechanical problem. At 2:09 p.m., Jan Magnussen officially took the lead = a lead that Corvette Racing would not relinquish. The winning Corvette completed 355 laps, made 25 faultless pit stops, and won by a five-lap margin of victory.

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DETROIT - The brand-new Corvette C6-R race car will debut at the 12 Hours of Sebring in March 2005 after a full year of rigorous testing and development. The two-car, factory-backed Chevrolet sports car program will compete in the production-based GT1 class (formerly GTS) of American Le Mans Series as well as the legendary 24 Hours of Le Mans in France, a race where the Corvette has won its class for three out of the past four years. The new race car is the most technically advanced sports car ever developed by General Motors, culling years of experience from the dominant Corvette C5-R as well as the advancements brought forth from the next-generation Corvette C6 and Z06 production models.

Like the C5-R before it, the Corvette C6-R starts from production roots: the same hydroformed frame rails that roll down the assembly line at the Corvette plant in Bowling Green , Kentucky are sourced for the structure of the race car. With the new C6 production model measuring shorter in overall length (but with a longer wheelbase), race car engineers faced a new set of numbers in which to achieve their goals to make the car faster on the 180-mph Mulsanne Straight at Le Mans and other high-speed circuits.

Adding a rear wing and a front splitter enabled the team to develop a package that achieves a lift-to-drag ratio better than that of the C5-R. Through a combination of Computational Fluid Dynamic studies and on-track testing, the end result will be an aerodynamically balanced package, tunable to the low drag demands of Le Mans or the high downforce requirements of Mosport.

The phrase 'technology transfer' has never been more appropriate than when used to describe the matched set of Corvette C6-R and Corvette Z06. Lessons learned on the track have benefited the Z06, just as GM's vast resources have enriched the C6-R race car. Both cars are powered by 7-liter small-block V-8 engines with dry-sump lubrication systems, CNC-ported cylinder heads, titanium valves and connecting rods, forged steel crankshafts, and plate-honed cylinder bores. While the components and specifications of the street and competition engines are tailored to their specific environments, the thought process behind them is identical.

The same six drivers that piloted the C5-Rs to an historical undefeated season in 2004 will return to the track in 2005: Ron Fellows, Johnny O'Connell and Max Papis will drive the #3 Corvette C6-R and Oliver Gavin , Olivier Beretta and Jan Magnussen will drive the #4 Corvette C6-R.


 

2006 Mercedes- Benz SLK 55 AMG Special Series




In Detail
price               107 300 Euros
engine            V8
power             298.3 kw / 400 bhp @ Not Available rpm
bhp/weight   267.56 bhp per weight
drive wheels  RWD
body / frame Unit Steel w/GRP Fenders
front brakes   Composite Discs
rear brakes     Discs
front tire size 235/35 ZR 19
rear tire size  265/30 ZR 19
weight             1495  kg / 3296 lbs
transmission  7-Speed Speedsift
0 - 60 mph     4.4 seconds


Affalterbach, Jun 09, 2006-Mercedes AMG has developed an exclusive and distinctly puristic special series SLK. With the AMG 5.5-litre V8 engine enhanced to 294 kW/400 hp and 520 Newton metres, numerous lightweight construction components, carbon hardtop, 19-inch AMG forged wheels, AMG height-adjustable torsion sports suspension and AMG high-performance composite brake system the special SLK 55 AMG demonstrates even more convincingly its sports talent.



Wide, stocky and low slung - the first impression already makes it clear that the SLK 55 AMG is something very special. The front of the car has a restyled AMG front apron with large air intakes which supply the additional transmission oil cooler and the high-performance steering gear oil cooler with sufficient fresh air. New side air outlets of black carbon ensure an effective flow through of the larger engine oil cooler. The front fenders which are now wider are made of the ultra-light carbon-fibre-reinforced-plastic (CRP) and have black out-lined air outlets.



The non-retractable hardtop of the two-seater is also made of CRP; the black central part with carbon fibre structure provides attractive optical effects. Dis-carding of the vario roof and the complete roof hydraulics has not only enabled a lowering of the centre of gravity, but has also resulted in a notable reduction of weight - the puristic special series of the SLK 55 AMG is with a curb weight of 1,495 kg according to EC standard 45 kg lighter than the basic vehicle. This means that the power/weight ratio has improved from 4.3 to 3.7 kg/hp.



Appropriate to the optimised weight there is a redeveloped AMG 5.5-litre V8 engine under the bonnet with a maximum performance of 294 kW/400 hp, as well as a 520 Newton metres torque. A modified air intake, AMG sports air filter as well as newly developed fan-type exhaust pipes provide an efficient gas cycle and enable that the eight-cylinder reacts more promptly to accelerator pedal movement - which is acoustically noticeable due to the unmistakable V8 sound. The combination of a lower vehicle weight and a high-performance AMG eight-cylinder engine guarantees first-class driving performance: the acceleration from zero to 100 km/h requires only 4.5 seconds (standard vehicle: 4.9 secs.), after 15.5 seconds the SLK 55 AMG already achieves 200 km/h (standard vehicle 17.5 secs.). Power transmission is supplied by the AMG SPEEDSHIFT 7G-TRONIC with manual drive program and AMG aluminium shift paddles on the steering wheel. The chassis and brake system are the ideal partners for the dynamic drive package. For example, the AMG height-adjustable torsion suspension, including adjustable shock absorbers, which has been optimised on the racetrack, allows amazing cornering speed. A brace in the engine compartment provides additional rigidity and more lateral dynamics. The special series SLK 55 AMG has ultra-light AMG forged light alloy-wheels with mixed-size tyres in sizes 235/35 ZR 19 (front) and 265/30 ZR 19 (rear) – as an alternative, optional special sports tyres are available without extra charge. Perfect deceleration is guaranteed by the AMG high-performance brake system with larger composite discs on the front axle.



The racing design is consistently continued in the interior: two specially developed AMG sport bucket seats without side airbags in black pearl velour with silver AMG logo offer the best lateral support, the new AMG ergonomic sports steering wheel in leather and Alcantara enables perfect control of the vehicle. Ample carbon fibre on the door panel lining as well as on the trim parts give the interior the functional atmosphere of a real racing car.



DThe first models of the unlimited AMG special series will be supplied to customers as of July. The price in Germany is 107,300 euros (incl. 16% VAT).

 

Porsche Carrera GT



In Detail
price                    $440 000 USD
engine                  Aluminum, 68 Degree, Water Cooled V10 w/Dry Sump Lubrication
position               Mid Longitudinal
aspiration            Natural
valvetrain           DOHC 4 Valves per Cyl w/VarioCam
fuel feed              Sequential Multi-Point Fuel Injection
displacement     5733 cc / 349.8 cu in
bore                    98 mm / 3.86 in
stroke                 76 mm / 2.99 in
compression       12.0:1
power                  456.4 kw / 612 bhp @ 8000 rpm
hp per litre         106.75 bhp per litre
bhp/weight         443.48 bhp per weight
torque                  589.78 nm / 435 ft lbs @ 5750 rpm
redline                 8400
drive wheels        RWD w/ASR 5.7, LSD
body / frame       Carbon Fibre Body over Carbon Fiber Reinforced Plasitc Frame
front brakes         Internally Vented & Cross Drilled Ceramic Composite Discs w/6-Piston Calipers, ABS
f brake size           380 mm / 15.0 in
rear brakes           Internally Vented & Cross Drilled Ceramic Composite Discs w/6-Piston Calipers, ABS
r brake size           380 mm / 15.0 in
front wheels F      48.3 x 24.1 cm / 19 x 9.5 in
rear wheels R       50.8 x 31.8 cm / 20 x 12.5 in
front tire size       265/35ZR19 Michelin Pilot Sport 2
rear tire size         335/30ZR20 Michelin Pilot Sport 2
steering                  Rack & Pinion w/Power Steering
f suspension          Double Wishbones w/Inboard Springs & Dampers
r suspension          Double Wishbones w/Inboard Springs & Dampers
weight                    1380 kg / 3042 lbs
wheelbase              2730 mm / 107.5 in
front track             1612 mm / 63.5 in
rear track               1587 mm / 62.5 in
length                      4613 mm / 181.6 in
width                       1920 mm / 75.6 in
height                      1166 mm / 45.9 in
transmission           6-Speed Manual w/Two-Plate Ceramic Dry Clutch
gear ratios               3.20:1, 1.87:1, 1.36:1, 1.07:1, 0.90:1, 0.75:1
final drive               4.44:1
top speed                329.9 kph / 205.0 mph
0 - 60 mph             3.8 seconds
0 - 100 mph            6.9 seconds
0 - 1/4 mile             11.4 seconds
epa city/hwy           15 mpg


After two years, the Carrera GT Concept first seen at the 2001 Paris Auto Salon is finalized by its production counterpart. Released at the 2003 Geneva Auto Show, the Carrera GT represents Porsche's first limited production supercar since the 959 and one of the few available products that rival the Ferrari Enzo.



Motivation for the Carrera GT came from Porsche's successful motor sports program. A decision to start the Carrera GT as a proposal for Le Mans came after the last Porsche victory there in 1998 . The new car would homage to cars including the 917 and GT1. Both these cars have won Le Mans and both lent their technical developments to the Carrera GT.



Unlike the 911, which has carried the company for four decades, the Carrera GT has a new style and substance. Its styling, thankfully unchanged from Paris show car, departs from the traditional Porsche design language which the 959 couldn't escape.



Under the skin, the car uses familiar hallmarks of motor sport. combining light weight design and a low-centre of gravity with a mid-mounted engine. Having a mid-mounted engine helps the Carrera GT achieve better undertray airflow not possible on the rear-engine 911. If one aspect of the Carrera GT was to filter down to the 911, it could be this mid-ship layout.



A new V10



Powering the Carrera GT is 68-Degree V10 originally intended for Le Mans. It has been modified by Porsche engineers to ensure more power and reliability. Such revisions include a larger displacement offers more torque and more driveability.



This engine is placed mid-ship in the chassis within a three-point carbon subframe. This is unlike Paris Show Car which featured its V10 as a load bearing structure within the chassis. Had Porsche not used a subframe, the noise leakage would have hampered comfort.



The intake system is equipped with Porsche's VarioCam technology found on the current 996 range. VarioCam continuously adjusts the angle of the intake camshaft to optimize performance and output.



Making the engine as light as possible was a primary goal. A light alloy crankcase and titanium connecting rods help the engine have a weight of 452 lbs (205 kg). Compare this to the Enzo's V12 weighing in at 496 lbs (225 kg).



6-Speed with a Ceramic Clutch



Power is transferred to the rear wheels through a newly developed six-speed manual transmission. Attached is a conventional clutch which has long since disappeared in both the Ferrari Enzo and Mercedes-Benz SLR. Porsche have made the clutch a technical highlight of the car by reducing its size and weight by several degrees.



Called Porsche Ceramic Composite Clutch (PCCC), this two-plate clutch is made of ceramic composites. Such materials not only help reduce the rotational masses of the clutch by a factor of ten, but offer less wear than conventional material. Combined with a lightweight flywheel rotational mass of the engine is exceptionally light.



Another highlight of this clutch is it's short diameter of only 6.5 inches (165 mm). At such a height the transmission and engine are very short and mounted low in the chassis. Just how low? Well the crankshaft rotates just 4.0 inches (102 mm) from the floor and the transmission actually sits lower than the rear differential.



CFP Chassis



Providing a basis for the Carrera GT is a carbon fiber monocoque with carbon-fiber-reinforced plastic (CFP) sub frames. Among the carbon body and carbon frame, metal pieces are few and far between. For instance on the chassis, the front rails, a-post inserts, fuel cell and suspension are the only major non-carbon elements.



The chassis is manufactured by a company called ATR. They are specialist Italian carbon fiber manufacturer which coincidentally make the tubs for the Ferrari Enzo. Production at ATR is two complete chassis per day.



A carbon rear sub frame isolates the entire drive train and rear suspension from the chassis. Having the engine completely supported CFP materials is new concept to production car manufacturing. It was concept developed by Porsche's Motor Racing Division and is subject to patent.



Suspension elements include double wishbones with inboard damper and springs on all four wheels. The inboard dampers and springs are actuated by pushrod and dampers like the setup used by every Formula One constructor.



Braking on all four corners is executed by the capable Porsche Ceramic Composite Brake (PCCB) system and for the first time on fifteen inch rotors. Consisting of ceramic discs and composite pads the system is lightweight and resistant to corrosion. PCCB reduces the unsprung weight of the braking system by fifty percent. Four channel ABS comes standard.



Attached to the braking system are forged magnesium wheels which weigh less than the tires wrapped around them. Michelin makes the only tire approved for the Carerra GT. They feature a soft compound rubber on the outer one third of the tread. It is suggested by Porsche that these tires need replacement every 15000 miles.



Aerodynamics



A large rear wing provides down force at the rear of the car. As the car reaches 75 mph (120 km/h) it electro-hydraulically raises an additional 6 inches (16 cm) for increased stability. At top speed the combined down force of the front and rear wheels total 639 pounds (290 kgs).



Apart from the wing, most of the Carrera GT's down force comes from its under tray. The entire tray is manufactured from carbon fiber and is attached to the chassis, engine mounts and crash structure. Creating down force with such a device is efficient as it does not impair the car's drag coefficient. A diffuser and air flow ducts provide additional ground effect.



Further aerodynamic attention is applied to the lower wishbones. They are made of efficiently shaped steel tubes which do not interfere with the aerodynamics underneath the car.



Electronics



To ensure control under all situations, the Carrera GT has a four channel anti-lock braking system and anti-spin control (ASC) to prevent excessive wheel spin. Traction control is standard. 'Should he/she wish to enjoy the thrill of dynamic driving of the highest racing standard the driver can switch off the complete traction control function by pressing a button in the centre console.' says Porsche.



Comfort



Porsche describe the Carrera's clean interior as a function-oriented ambience and a cockpit free of all extraneous detail. Only high-tech materials such as carbon, magnesium and leather adorn most surfaces.



Information is clearly presented in a classic Porsche instrument cluster which replaces the LCD screen featured on the concept car. The car also uses the 911 steering wheel which doesn't follow the F1 trend to stick as many functions on the wheel as possible. This old-school approach is a refreshing change, contributing to the GT's ambiance and ensuring it will remain a timeless design.



Extending into the dash is a centre console covered in magnesium. Attached sits a birch/ash shifter which is the only piece of wood found in this carbon-laden car. It specifically pays homage to Porsches 917 which sported a balsa-wood gear lever. Balsa was the optimum material for the job, it was extremely light, but most importantly added to the character of the 917.



Amenities such a Bose stereo system and air conditioning are optionally offered.



For closed top driving, two carbon fiber panels can be attached to the roof. At a low weight of just 6.4 lbs (2.4 kgs) each, these panels are easily removable and can be stored in the front luggage compartment.



Conclusion



Comparison between the Carrera GT and Ferrari Enzo is inevitable. Having 48 more horsepower (35.8 kW), and weighing 33 lbs (15 kgs) less, the Enzo easily wins on the straight line. The Carrera GT on the other hand, features much more down force and might possibly catch up in the esses. In any case, if either car is superior, the margin is so narrow that both cars can really take the cake.



It is also important to mention that the Carrera GT isn't the fastest supercar. Had Porsche tried to chase the McLaren's performance figures, production (planned at 1500 cars), profitability and comfort would have suffered.

 

The Mercedes -Benz SLR McLaren





In Detail
price $455 000 USD
engine 90 Degree AMG V8 w/Dry Sump
position Front-Mid Longitudinal
aspiration Screw-Type Compressor w/Two Charge-Air Coolers
valvetrain SOHC, 3 Valves per Cyl
displacement 5439 cc / 331.9 cu in
bore 97 mm / 3.82 in
stroke 92 mm / 3.62 in
compression 8.8:1
power 466.8 kw / 626 bhp @ 6500 rpm
hp per litre 1 15.09 bhp per litre
bhp/weight 354.07 bhp per weight
torque 780 nm / 575.3 ft lbs @ 3250-5000 rpm
body / frame Carbon Fibre & Compsite Body & Chassis
front brakes Internally Vented Carbon Discs w/8-Piston Calipers, ESP, SBC
f brake size 370 mm / 14.6 in
rear brakes Solid Carbon Discs w/4-Piston Calipers, ESP, SBC
r brake size 360 mm / 14.2 in
front wheels F 45.7 x 22.9 cm / 18 x 9 in
rear wheels R 45.7 x 29.2 cm / 18 x 11.5 in
front tire size 245/40 ZR 18
rear tire size 295/35 ZR 18
steering Rack & Pinion w/Speed Sensitive Assist
f suspension Double Wishbones w/Anti-Roll Bar
r suspension Doube wishbones
weight 1768 kg / 3898 lbs
wheelbase 2700 mm / 106.3 in
front track 1638 mm / 64.5 in
rear track 1569 mm / 61.8 in
length 4656 mm / 183.3 in
width 1908 mm / 75.1 in
height 1261 mm / 49.6 in
transmission 5-Speed Auto w/Speedshift System
gear ratios 3.56:1, 2.19:1, 1.41:1, 1.00:1, 0.831:1
top speed 334 kph / 207.5 mph
0 - 60 mph 3.6 seconds
0 - 100 mph 7.6 seconds
0 - 1/4 mile 11.6 seconds






The Mercedes-Benz SLR McLaren revives the glorious tradition of the SLR and marks the reawakening of Mercedes-Benz' passion for super sports cars. It is a passion which can be traced way back through automotive history and which was demon-strated with the Uhlenhaut Coupe. A contemporary interpretation of stylistic elements lifted from the original SLR and design details taken from the 2003 Formula 1 Silver Arrows allow the 21st-century SLR to form a bridge between the past and the future, bringing cutting-edge motorsport technology to the road, just as the inspirational SLR Coupe did in 1955.



The new super sports car allows Mercedes-Benz and its Formula 1 partner McLaren to showcase their collective experience in the development, construction and production of high-performance sports cars. This combination of knowledge and expertise is evident not only in the host of pioneering developments, impressive performance figures and superior driving characteristics of the SLR, but also in the extremely high levels of safety and practicality which it offers. These attributes come together to form the basis for an automobile with a very special charisma - an impressive synthesis of Mercedes tradition and innovation in every respect.



Just like its legendary predecessor of 1955, this SLR incorporates new technological developments which are ahead of their time. For evidence, simply take a glance under the bonnet at the Mercedes-AMG V8 powerplant. With its 5.5-litre displacement and screw-type compressor, the engine develops a peak output of 460 kW/626 hp and delivers its maximum torque of 780 Newtonmetres from 3250 rpm - a figure which remains constant across a broad engine speed range of up to 5000 rpm. With this kind of power under the bonnet, the Mercedes-Benz SLR McLaren delivers performance figures which are among the best in its class: this high-performance sports car takes just 3.8 seconds to sprint from 0 to 100 km/h, it passes the 200 km/h mark after 10.6 seconds, and from a standing start it takes just 28.8 seconds to reach 300 km/h. The two-seater has a top speed of 207 mph (334 km/h).



In the interests of optimum weight distribution, optimum dynamic handling and high stability on braking, the Mercedes-Benz SLR McLaren has a front mid-engined design. The V8 powerplant is mounted on a robust aluminium frame and has a low installation position. Water-type charge-air cooling, three valves per cylinder, dry sump lubrication and four metal catalytic converters are further special features of this powerful engine - an engine which already meets stringent EU 4 exhaust gas regulations which are not due to come into force until 2005.



Engine & Transmission



When developing the powerplant, the AMG engineers applied both the expertise they had acquired during their three-decade involvement in motorsport and the stringent standards of the Mercedes-Benz brand. After an extensive concept phase, they decided in favour of an 8-cylinder design with a 5.5-litre displacement, a cylinder angle of 90 degrees, a screw-type compressor and a crankshaft supported by five bearings.



The result is impressive: from a mere 1500 rpm, the SLR powerplant delivers torque of over 600 Newtonmetres, rising to 700 Newtonmetres at 2000 rpm. The maximum of 780 Newtonmetres is available from 3250 rpm and remains constant in a broad engine speed range up to 5000 rpm As the figures indicate, the new SLR is endowed with what is currently one of the most powerful engines to be found in a series-produced roadgoing sports car.



The design of the powerplant's oil cooling system is also based on experience gathered in the world of motor racing: a sophisticated dry sump lubrication system with an oil capacity of around eleven litres, combined with a five-stage oil suction pump and a two-stage oil pressure pump, ensures reliable lubrication under all on-road conditions. An important side effect of this technology is that, because of the dry sump lubrication, usually only used in motor racing vehicles, the engine is less tall and can therefore be installed at a lower level, allowing a low centre of gravity which benefits dynamic handling.



Following the usual practice at Mercedes-AMG, each SLR engine is manufactured by hand. In order to achieve the highest quality, the principle of 'one man, one engine' is applied. This means that each powerplant is the responsibility of one AMG engineer, who carries out the entire engine assembly process - from installing the crankshaft in the engine block and assembling the camshafts and the compressor to cabling.



Power from screw-type compressor



To ensure good cylinder charging, the engine has a mechanical compressor with two screw-type aluminium rotors which, in the interests of low friction losses, are Teflon-coated. The charger is so compact that the engine specialists were able to install it between the two cylinder banks of the V8 powerplant. Despite the space-saving design, its innovative technology allows a significantly higher charge pressure than conventional mechanical chargers because the two rotors achieve a top speed of around 23,000 revs per minute, forcing air into the air inlet of the 5.5-litre powerplant at a maximum pressure of 0.9 bar. This means that they compress around 1850 kilograms of air into the eight combustion chambers per hour - which is up to 30 percent more than the figure achieved by rival charging systems.



In order to ensure the greatest possible efficiency, the AMG engineers created an intelligent engine management system which regulates the operation of the screw-type compressor according to the engine speed and load. This means that the charger is only active when it is needed. Nevertheless, the system ensures that the maximum output is available as soon as the driver calls it up by stepping on the accelerator. When this occurs, the electronics of the engine management system trigger an electromagnetic coupling which immediately activates the compressor, which is powered by a separate poly-V-belt. Because the charger delivers its output in fractions of a second, even the most perceptive driver will not notice the phases without charger support. The charger system's air recirculation flap, opened under partial load, helps reduce fuel consumption.



Manual transmission program for racing car-style shift times



The five-speed automatic transmission, developed by Mercedes-Benz and already successfully used in several exceptionally powerful models, is also designed for high performance. It has been specially optimised for very high torque and also offers the driver the option of choosing between different shift characteristics. The transmission transmits the engine power via a finely balanced aluminium and steel powertrain to the differential and the rear axle.



The Speedshift system, developed by Mercedes-AMG for particularly sporty driving, offers even more functions in the new SLR. The driver can decide, for example, whether to leave the shift work to the automatic transmission or to shift gears manually. He or she can also select the shift speed, determining how sporty the gearshifts are. A rotary switch in the centre console offers a choice of three settings: Manual, Comfort and Sport. The activated programme is indicated in the instrument cluster display by the letters M, C or S.



Bodyshell



When it comes to body and safety technology the new Mercedes-Benz SLR McLaren yet again lives up to its reputation as an innovative force among today's Gran Turismos. High-tech materials from the field of aeronautical technology make their debut in a series-produced car here: carbon fibre is used for manufacturing the body, lending it its low weight and an exemplary rigidity and strength previously only achieved in Formula 1 race cars. The crash safety standards achieved using this innovative material are equally high.



Carbon fibre has been used to great effect in the aeronautical industry for some time. The rudder unit, vertical rudder, landing flaps and other parts of most airbuses are made from this material, in the development and series use of which the scientists at DaimlerChrysler Research played a significant role. Their expertise and the extensive experience of the Mercedes-Benz and McLaren experts in the field of race car design can now, for the first time, be seen in a series-produced car: the entire bodyshell and the doors and bonnet of the SLR are made from corrosion-resistant carbon fibre composite.



While offering the same strength as their steel or aluminium counterparts, carbon fibre components weigh up to 50 percent less than comparable steel components and up to 30 percent less than aluminium components. This makes carbon fibre composite the material of choice for manufacturing high-performance cars, because lower weight not only means lower fuel consumption but also outstanding transfer of power to the road. The lower the mass to be accelerated and braked, the better the agility. In fact, thanks to the extensive use of carbon fibre composites, the primary structure of the Mercedes-Benz SLR McLaren is around 30 percent lighter than the conventional steel construction of a comparable front mid-engined vehicle.



Carbon fibre composite offers significantly higher energy absorption



On top of this, the state-of-the-art lightweight material is also characterised by very good energy absorption. The figures here for carbon fibre composites are around four to five times higher than those for metal materials. Formula 1 constructors have been exploiting this quality for several years, manufacturing the crash structure of their race cars from carbon fibre composite. The result has been a significant fall in the number of serious injuries incurred in high-speed accidents in this top motorsportdiscipline.



The monocoque - or, to put it another way, the passenger cell - of the new Mercedes-Benz SLR McLaren is also made entirely from this high-tech material. In the event of a head-on, side-on or rearend collision, it offers the passengers a highly rigid and hence safe survival zone.



The first automated production of carbon fibre composite components



To date, carbon fibre composite components for racing cars and for the aeronautical and space industries have been manufactured by hand - a time-consuming process. The challenge for the Mercedes engineers was to use their experience in this field to develop automated methods of series production. To do this they divided the manufacturing process into separate stages, manufacturing of the preform being followed by impregnation with resin and hardening.



In order to allow extensive automation of the preform manufacturing process (the preform also being made from carbon fibre), the materials experts at Mercedes-Benz cast a glance at the work of their colleagues in the textile industry and adapted traditional manufacturing methods used in this sector, such as sewing, knitting, weaving and braiding, for the processing of high-performance carbon fibres.



To take an example, the web of the SLR's longitudinal members is formed from several layers of carbon fibre placed on top of one another and sewed together by machine. Once the piece has been cut to shape and the ends folded up to form a double T profile, the web blank is inserted in a polystyrene braiding core. This core element is clamped into a specially developed braiding machine, which braids together the longitudinal members from 25,000 extremely fine, individual carbon filaments, these being unwound simultaneously from 48 reels. This technology allows the fibre material to be braided around the core at a precisely calculated angle to create the required contour. Several layers are even laid on top of one another in certain areas, depending on the required thickness. An innovative method was developed for this process too.



In a further manufacturing process, a computer-controlled tufting machine joins the inner web to the braid of the longitudinal member. The braid core is removed and the preform of the longitudinal member is cut to the correct size. The preform is then injected with resin. Several, now patented, solutions had to be developed and tested in order to ensure short cycle times and high repeat precision for this manufacturing process - crucial qualities in series production. The manufacture of the complex fibre struc-ture of the longitudinal members using a braiding machine requires a cycle time of just twelve minutes, which illustrates the unit potential that this innovative manufacturing technology offers.



Suspension



Highly developed motor racing technology, high-performance control systems and cutting-edge materials - a unique combination which propels the Mercedes-Benz SLR McLaren into a new dimension in sports car dynamics, helping it to achieve top figures in three key areas: agility, active safety and comfort. In the process, the SLR suspension meets every criteria a discerning car driver would expect to find in a Gran Turismo with a Mercedes star.



The axle design bears the signature of experienced racing car developers, with double wishbone suspension at the front and rear. The lower struts are arranged so that, as the springs compress and when cornering at speed, the wheels have a negative camber. This ensures the best possible contact with the road in every situation. At the same time the axle technology prevents the front of the car from diving when braking heavily and the rear from diving when accelerating.



Aluminium was the key material for the developers of the new Mercedes-Benz SLR McLaren's suspension. The wishbones are made from forged aluminium, while the wheel mounts are cast in aluminium. In addition to a whole series of other advantages over conventional steel designs, the lightweight nature of the material allows the suspension to react significantly faster and to respond more sensitively.



The relatively long wheelbase (at 2700 millimetres) also contributes to the SLR's exemplary handling and makes itself noticed above all in the car's exemplary directional stability, while the large track width, combined with the low centre of gravity, allows high cornering speeds.



Springing/damping combinations at the front and rear axle and an anti-roll bar at the front complete the suspension structure. The anti-roll bar is positioned above the front axle and - as in Formula 1 - is controlled via rocker arms. This means that it does not take up any installation space which could impair the smooth line of the underbody - a vital factor when it comes to the sports car's outstanding aerodynamic properties.



The speed-sensitive rack-and-pinion power steering also corresponds with the in-telligent lightweight concept. In comparison with other steering systems, this design is characterised by a significantly lower weight. Thanks to its low installation position in front of the engine and the gear ratio of 12.6, the steering system re-sponds directly to the driver's commands and carries them out with high precision. The three-spoke steering wheel has a diameter of 380 millimetres and is fitted with an electric motor which allows it to be positioned to suit the individual driver. It can be adjusted by 60 millimetres for reach, and the height of the steering wheel can be varied by 2.7 degrees



SBC and ESP



The electrohydraulic braking system, Sensotronic Brake Control, a milestone in car technology, forms part of the standard equipment of the Mercedes-Benz SLR McLaren. It processes data from various sensors regarding the current status of the vehicle and can use this to calculate and apportion the optimum brake pressure for each wheel at lightning speed. A high-pressure accumulator holds the brake fluid, which flows into the system at a pressure of 140 to 160 bar. This also optimises the function of the Electronic Stability Program (ESP), which keeps the SLR safely on track by applying targeted brake impulses to the individual wheels and/or reducing the engine torque. Here too SBC offers the advantage of higher dynamism and precision: thanks to even faster and even more finely metered brake impulses from the SBC high-pressure accumulator, ESP can stabilise a swerving vehicle comfortably at an early stage.



The coordination of this system with the Electronic Stability Program (ESP) was a particular challenge for the engineers of the high-performance sports car. Their aim was to adapt the dynamic handling control system to the vehicle's distinctly sporty performance yet maintain the usual safety standards, achieving an ideal compromise between outstanding dynamic handling and exemplary directional stability. Here too SBC demonstrated its strengths, being able to deliver adequate braking power at lightning speed in every on-road situation, thanks to its sophisticated sensors and the high-pressure accumulator, making a key contribution to the precision handling of the SLR. It was therefore possible to allow a very sporty driving style with controlled side-slip angles in keeping with the character of the high-performance car without compromising active safety. On top of this, SBC significantly enhances active safety in critical situations.



Ceramic brake discs for top performance



Mercedes-Benz has optimised the outstanding properties of the Sensotronic Brake Control system in the new SLR with a braking system which also marks a technological high-point in a high-performance car: at the front and rear axle of the cutting-edge swing-wing door vehicle, brake discs made from fibre-reinforced ceramic ensure reliable deceleration. Their development is based on the one hand on the results of DaimlerChrysler materials research and on the other on Mercedes-AMG's experience of high-tech brakes in touring cars and GT sport. Here Mercedes-Benz yet again underlines its leading role in the development of groundbreaking technologies for car production.



In manufacturing the brake discs, the carbon fibre, powdered carbon and resin are pressed into shape at high pressure and baked with a silicon infiltration at temperatures of around 1500 Celsius to form the ceramic. The advantages of this composite material are considerable: in addition to being characterised by an extremely sensitive response, the Mercedes-Benz SLR McLaren's brake discs demonstrate a high temperature-resistance of up to 1000 Celsius, which produces a fade-resistance when braking at high speed never before achieved in a series-produced car. The result is brake power of up to 2000 hp.



Adaptable rear spoiler as airbrake



The outstanding performance of the SLR is also aided by the adaptable spoiler - known as the airbrake - in the boot lid. If the driver steps heavily on the brake pedal, the rear spoiler rises to an angle of 65 degrees, boosting the braking effect by producing greater aerodynamic drag. When braking from high speeds, it lends the SLR outstanding stability.



In most situations the electronics control the airbrake as required. However, the driver can also opt to take control of the adjustments using the switch in the centre console, manually

 

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