New Mercedes-AMG GT R Developed in the “Green Hell”
Mercedes-AMG continues to grow and is expanding the top end of its product range with the introduction of the new AMG GT R. “With the new AMG GT R, we have reached the next level of driving performance. This road-going sports car with motor-racing genes and innovative technical solutions offers an ultimate driving experience that allows people to feel our motorsport origins in every fibre. It combines the driving dynamics of our AMG GT3 racing car with the everyday practicality of the AMG GT. Those with petrol in their veins will be thrilled by the radical longitudinal and lateral acceleration, the precise turn-in, and the sensational grip. We have modified all performance- relevant components and linked them together intelligently for maximum driving dynamics,” says Tobias Moers, CEO of Mercedes AMG GmbH.
The third member of the AMG GT family is the new spearhead of the AMG model range. Featuring pioneering technologies, the AMG GT R was designed with racetrack use firmly in mind. Its development was largely based on vast motor- racing experience in AMG GT3 customer sport and the German Touring Car Masters. Figures such as 3.6 seconds from zero to 100 km/h and a top speed of 318 km/h, combined with the outstanding driving dynamics, will undoubtedly translate into extremely fast laps on the racetrack. The new exclusive colour “AMG green hell magno” alone establishes a visual link to the “Green Hell”, the nickname for the legendary “North Loop” of the Nurburgring, emphasising that the car’s roots are firmly embedded in the racetrack. Sharpened racetrack performance comes courtesy of the intelligent lightweight construction incorporating aluminium and carbon, specific reinforcements in the body shell, the uprated twin-turbo V-8 engine with the specifically adapted seven-speed dual-clutch transmission, the innovative aerodynamics with active components, and the new suspension with active rear-wheel steering and uniball joints.
The concept with front mid-engine and transmission in transaxle configuration on the rear axle, a tried-and-tested feature of the AMG GT and AMG GT S, makes for a beneficial rear-biased weight distribution of 47.3 to 52.7. In conjunction with the vehicle’s low centre of gravity, this translates into extremely agile handling and permits high cornering speeds. With a power-to-weight ratio of 2.66 kilograms per hp, the Mercedes-AMG GT R takes up pole position in its segment.
Close collaboration between design and aerodynamics experts
Aerodynamics engineers and designers worked together more intensively than ever during development of the new AMG GT R. The AMG design idiom of “Dynamic Presence” forms the basis for the far more expressive overall appearance and the very distinct look. Form follows function, and function supports form: All elements have an inherent technical benefit and contribute to the enhanced driving dynamics, while the aerodynamics experts have made the designers’ wishes a reality. This networking even resulted in an innovation that now has a patent pending.
The design of the AMG GT R embodies sensuous purity—hot & cool. Apart from the powerfully sculpted body and the motorsport components, the new AMG Panamericana grille is a real eye-catcher. This unique feature also comes from the world of motorsport and is celebrating its standard-production première in the AMG GT R: Its 15 chrome-plated vertical fins cite the look of the new AMG GT3 racing car. The basic form of the new radiator grille goes back to the Mercedes Benz 300 SL racing car that won the legendary Panamericana road race in Mexico in 1952.
Unbridled forwards thrust even when stationary: the front end
The low-slung front section and the forwards-inclined radiator grille create a distinctive “shark nose” impression and make the car appear to sit lower on the road. At the same time, this shape lowers the vehicle’s back-pressure point, enhancing the flow of cooling air and the car’s aerodynamic performance.
The more V-shaped arrow-like appearance of the front end also enhances the dynamic looks, thus embodying the uninhibited forward thrust of the AMG GT R even before it moves. A front fascia featuring a completely new-look jet-wing design (based on the A-wing) emphasises the feeling of width and lends the car a more road-hugging appearance. In terms of their shape, the large outer air intakes in the front fascia are reminiscent of jet engines. They ensure that the increased cooling-air requirements of the AMG GT R drive system are met. For this reason, they sport two aerodynamically shaped horizontal fins in place of meshes and as a result route the airflow to the radiators without loss.
The wide front splitter reduces lift at the front axle. Additional Air Curtains on the outside of the front fascia calm the airflow, improving the Cd value of the AMG GT R. Thanks to their narrow, vertical openings, the Air Curtains also guide the air specifically towards the wheel arches, optimising the flow properties in this area. To ensure ideal airflow through the double wheel arch radiators, the AMG GT R additionally features new and unique wheel arch liners with special cooling- air slits.
All-new active aerodynamics profile in the underbody
A special engineering feat is the completely new active aerodynamics profile, which is concealed almost invisibly in the underbody in front of the engine. At a speed of 80 km/h in RACE mode, this carbon component, weighing only about two kilograms, automatically moves downward by about 40 millimetres and changes the airflow considerably. This process results in what is known as the Venturi effect, which additionally “sucks” the car onto the road and reduces the front-axle lift by around 40 kilograms at 250 km/h.
The driver can feel this in the steering: the AMG GT R is even more precise to steer when cornering at high speed and exhibits even better directional stability. Especially during fast cornering and under high lateral acceleration, the AMG GT R delivers far more agile response with clear steering-wheel feedback while remaining easily controllable at all times.
In addition, the drag coefficient is improved. As a result, the downforce on the rear axle remains at an unchanged high level.
This innovation was developed using computer simulation at first and then optimised during many hours in the wind tunnel. The results were confirmed in extensive test drives, including on the North Circuit of the Nurburgring. The new- look aerodynamics profile is barely visible on the underbody and thus blends in harmoniously with the overall silhouette.
When the electrically operated profile is extended, the radiator air outlet opens at the front end and precisely guides the air flow towards the double rear diffuser, which therefore also benefits from an optimal flow of air. This improves the handling stability of the rear axle while reducing the temperature level of the hotspots at the rear. At the same time, the aerodynamics package ensures optimised stopping power by routing more cold air to the wheel discs specifically. To protect against damage, the component is spring-mounted and can therefore flex upwards easily.
Powerful and long: the side view
The front wings of super-light carbon add a total of 46 millimetres to the width of the AMG GT R at the front and make room for the wider track and large wheel/tyre combinations. The powerfully sculpted wings emphasise the longitudinal dynamics in addition. A further distinguishing feature is the special wing signet featuring a fin and a large air outlet through which the waste heat from the engine bay flows. This fin is perforated and incorporates the AMG diamond logo with five slats.
The side view additionally benefits from the new, optional AMG Performance forged wheels in matt black. The especially lightweight 10-spoke wheel is exclusive to the AMG GT R and its highly elaborate design includes a drop-centre rim, a milled groove and two high-sheen rim rings of different width. There are size 10.0 J x 19 ET56 wheels at the front and 12.0 J x 20 ET52 at the rear. The lightweight design of the wheels has three advantages: it reduces the overall weight, the rotatory mass and the unsprung masses. Efficiency and performance are enhanced, while the wheel suspension and steering deliver even more precise response, all of which also has a positive effect on the chassis and suspension control systems.
The wheels afford a clear view of the brake callipers, which are painted in yellow exclusively for the AMG GT R. New side sill panels make the vehicle look even lower stance on the road, while inserts in high-gloss black set an individual tone. The same applies to the high-gloss black caps on the housings of the door mirrors.
Emphasis on width and aerodynamic optimisation: the rear end
The rear end also features numerous, conspicuous innovations: The new aluminium side walls widen the rear of the AMG GT R by a total of 57 millimetres, creating space for the larger 20-inch wheels and the wider track. Both measures make for improved traction while allowing higher cornering speeds.
The wider design of the rear fascia with large outer vent openings and vertical swaging improves the airflow at the rear end, as does the double diffuser. The overall heat dissipation of the silencers is optimised as the warm air is exhausted by the double diffuser while driving.
A small air outlet is incorporated between the tail lamps for additional dissipation of the heat generated by the rear silencer. A further distinguishing feature of the AMG GT R is the large exhaust tip with centre spar, which is centrally positioned in the rear fascia. It is flanked by two more black exhaust tips on left and right in the diffuser.
The large rear wing is rigidly mounted on the hatch and increases the downforce on the rear axle. The aerofoil mounts are painted in vehicle colour whereas the blade is finished in high-gloss black. Depending on the type of use or racetrack conditions, the precise angle of the blade can be adjusted manually yet another technique also used in motorsport.
The result: all of the aerodynamic measures combined increase the surface contact at top speed by 155 kilograms compared with the AMG GT. The new AMG GT R therefore offers maximum grip, perfect drivability and a powerfully proportioned design that integrates the aerodynamic functions harmoniously.
Individual set-up: AMG coil-over suspension
The suspension of the new AMG high-performance sports model is also systematically designed for racetrack use. Wishbones, steering knuckles and hub carriers on the front and rear axle are manufactured entirely out of forged aluminium in order to reduce the unsprung masses. The double-wishbone concept locates the wheel firmly, with minimal elastic movements. The high camber and toe-in stability results in high cornering speeds and also provides the driver with an optimum feel for the road when cornering at the extreme limits.
The uniball spherical bearings on the lower wishbones of the rear axle are also inspired by motorsport. They are significantly more wear-resistant than wishbone bushings and due to their design have no play, which means toe-in and camber do not change even under high loads. As a result, the AMG GT R can be driven with even more precision.
The new AMG coil-over suspension was designed specifically for the AMG GT R. Like in professional motorsport, drivers can select their personal set-up and infinitely adjust the spring pre-load manually. This makes it possible to influence the dive and roll behaviour as well as the grip of the AMG GT R precisely as needed to tailor them to personal preferences or to the particular racetrack.
The coil-over suspension is combined with the AMG RIDE CONTROL continuously variable, adaptive damping system. The system is electronically controlled and automatically adapts the damping on each wheel to the current handling situation, the speed and the road conditions. The damping characteristics are modulated rapidly and precisely by two separate valves for the rebound and compression forces in the dampers. A harder damping rate, for example when cornering and braking, effectively reduces rolling movements. The continuous adjustment of the damping to the current speed also ensures the best possible road contact even at high speeds, thus enhancing safety.
Agility and stability: the active rear-wheel steering
The new AMG GT R is even more sensitive to steering inputs thanks to standard- fit active rear-wheel steering, which is being used for the first time on a Mercedes-AMG model. The system offers an ideal combination of agility and stability handling characteristics that are normally in direct conflict.
Two steering actuators replace the conventional control arms on the rear axle of the AMG GT R. At the heart of the system are two electro-mechanical actuators (electric motors with jackscrew) that are not mechanically connected to the steering wheel. This “by-wire” system adjusts the rear wheels within a predefined operating map by means of electronic control. The maximum toe angle change on the rear wheels of the AMG GT R is 1.5 degrees.
Up to a speed of 100 km/h, the rear wheels are turned in the opposite direction to the front wheels, corresponding to a virtual shortening of the wheelbase. The advantage of the AMG GT R is far more agile when steering into bends, resulting in even greater driving enjoyment and less steering effort especially on small and winding roads, narrow racetracks on which there are multiple changes in direction, or slalom courses. Further benefits include increased manoeuvrability and a smaller turning circle in everyday driving situations such as when turning or parking.
Once the speed of the AMG GT R exceeds 100 km/h, the system turns the rear wheels in the same direction as the front wheels, corresponding to a virtual lengthening of the wheelbase and improving handling stability. At the same time, the lateral force on the rear wheels builds up considerably faster when changing direction, which makes the response to steering inputs quicker. Drivers also notice that the AMG GT R delivers massive grip on the rear axle and strong stability during fast changes in direction without the otherwise perceivable twitching effect at the rear end.
The active rear-wheel steering not only improves cornering, it also assists the driver in the event of sudden evasive manoeuvres and thus enhances active safety, This makes the AMG GT R easier to control at the limit.
Ready to race: the interior design
To give the driver of the new AMG GT R ideal conditions in which to drive, the interior is also strongly inspired by motorsport. Extremely light, manually adjustable AMG sports bucket seats upholstered in nappa leather and DINAMICA microfibre come as standard. They offer the necessary lateral support even in extreme driving manoeuvres. Alternatively, tried-and-tested AMG performance seats can be ordered as an option at no extra cost. The optional yellow seat belts, dials with yellow highlights, the AMG Interior Piano Lacquer package and special controls, including those for the new AMG TRACTION CONTROL, underline the unique standing of the new AMG GT R.
The wide-looking dashboard is reminiscent of a powerful wing and continues the aviation design theme. Four central spotlight-style vents and the individual vents at the right and left ends of the dashboard reinforce this impression. In conjunction with the high beltlines, the concave-shaped door panelling and the dynamic centre console, the AMG GT R comes across as the ultimate driving machine and consummately integrates the driver into the cockpit thanks to the low seat position.
The shape of the dominant centre console reminiscent of a NACA air intake and the authentic materials suggest that it has been adopted directly from motor racing. Positioned centrally, the free-standing central display is another eye-catching feature. Attention to detail is also echoed in the AMG DRIVE UNIT controls: They are arranged like eight cylinders in a V layout, emphasising the powerful and hi-tech impression made by the centre console.
More equipment, less weight: AMG Lightweight Performance
One key factor that influences the performance of a sports car is weight. Mercedes-AMG uses an intelligent material mix for the structure of the AMG GT R: various aluminium alloys for the chassis and body, steel for the boot lid and magnesium for the front deck. This extremely light element at the front reduces the inertia ahead of the front axle, thus improving the vehicle’s agility.
The weight-optimised spaceframe is made of die-cast and extruded aluminium sections. The high bending and torsional strength of the entire design enables extreme linear and transverse forces from the drivetrain and suspension to be absorbed and transferred. Unwanted flexibility is thus reduced, with the vehicle responding precisely and directly. The result: The driver experiences a sports car with maximum dynamics that responds with outstanding precision.
More power, more torque, faster response: the engine
The heart of the new high-performance athlete is pumping stronger than ever: the AMG 4.0-litre twin-turbo engine in the AMG GT R has an output of 430 kW(585 hp), which is 55 kW (75 hp) more than the previous top-of-the-range engine in the GT S. The peak torque of 700 Nm is available between 1900 and 5500 rpm.
The increase in performance was achieved with the help of new turbochargers with modified compressor machining, smaller wastegate aneroid capsule and sharpened engine mapping. The boost pressure supplied by the turbochargers has been increased from 1.2 bar in the AMG GT to 1.35 bar. In addition, the exhaust ports have been optimised and the compression ratio modified. The entire combustion process has been retuned.
A correspondingly modified application of the accelerator characteristics, charge-pressure build-up and transmission parameters ensures that the engine responds to load changes even more spontaneously and that gear changes are effected with even greater speed. The fact that the two-mass flywheel is 0.7 kilograms lighter than its counterpart in the AMG GT S likewise contributes to the highly agile impression.
The eight-cylinder unit thrills with its spontaneous response, precisely measured power output and linear power delivery with powerful thrust in all engine speed ranges, all of which makes the car far easier to control when driving at the limit. To make this possible, the sophisticated engine control electronics also take into account the current driving status and control the accelerator characteristics as a function of the occurring lateral forces also.
The AMG 4.0-litre V-8 engine features the tried-and-tested twin turbochargers, which are not mounted on the outside of the cylinder banks but rather inside the V configuration – experts call it a ‘hot inside V’. The benefits are: a compact engine design, spontaneous response from the turbochargers and low exhaust gas emissions thanks to optimum air flow for the close-coupled catalytic converters. This basic principle of the new AMG V-8 family has been further optimised for the AMG GT R and enables further improved performance. The maximum charge pressure is 1.35 bar; the turbochargers have a maximum speed of 186,000 revolutions per minute.