Published on May 14th, 2018 | by Subhash Nair0
Mercedes-AMG GT S Now Available as a Roadster
In time for the spring, Mercedes-AMG is extending its sports car portfolio with the new AMG GT S Roadster as an attractive open-air model. With this latest addition the AMG GT family now has a dozen members: four two-door Coupés, three Roadsters, two customer sports racing cars and three four-door Coupés. The basis for the high Driving Performance of the new AMG GT S Roadster is the combination of a lightweight aluminium spaceframe, a V8 biturbo engine, a seven-speed dual clutch transmission, a rear axle locking differential and a sport suspension with aluminium double wishbone axles.
Compared to the AMG GT Roadster, the AMG GT S Roadster is rendered even more dynamic by numerous modifications to the engine, suspension, brakes, design and interior. This positions it between the AMG GT Roadster and the even more powerful AMG GT C Roadster, now providing a choice of three open-top two-seaters.
Muscular power unit for a top speed of over 300 km/h
The AMG 4.0-litre V8 biturbo in the AMG GT S Roadster delivers an output of 522 hp and maximum torque of 670 Nm. This is available over a wide engine speed range from 1900 to 5000 rpm. The eight-cylinder power unit delivers muscular performance in all engine speed ranges, combined with high efficiency for low fuel consumption and emission levels. A sprint from standstill to 100 km/h is absolved in 3.8 seconds. The dynamic power delivery continues right up to the top speed of 308 km/h.
The two turbochargers of the V8 are not positioned on the outside of the cylinder banks, but inside the cylinder “V”. Advantages: a compact engine design, spontaneous response of the turbochargers and low exhaust emissions thanks to optimal airflow to the near-engine catalysts. The dry sump lubrication also ensures the oil supply even with high lateral forces and allows the engine to be installed lower, thus moving the centre of gravity closer to the road and forming the basis for high lateral acceleration.
Power transfer is based on the combination of a front mid-engine and the AMG SPEEDSHIFT DCT 7G sport transmission in a transaxle arrangement, combined with a torsionally rigid torque tube. Thanks to the wide gear ratio spread, the decidedly high torque of the V8 biturbo engine can be used to optimum effect. The weight distribution is also ideal for optimum driving dynamics at 47 (front) and 53 (rear) percent.
Standard equipment: Electronically controlled rear differential
As standard, the AMG GT S Roadster is equipped with an electronically controlled locking differential at the rear axle, which is integrated into the compact transmission housing. Its sensitive and fast control raises the critical limit of vehicle dynamics to a new level. It not only further improves the traction of the drive wheels, but also increases the critical cornering speed. The result is that the driver is able to accelerate out of corners earlier and with more power thanks to the improved traction. The vehicle remains more stable when braking from high speed, while the limited-slip differential also improves traction from rest.
The greatest benefit of the electronic rear-axle limited-slip differential is the even more sensitive and proactive control, which pushes the critical threshold higher, making it even easier to drive at the vehicle’s limits. To deliver optimum cooling, the housing of the limited-slip differential has additional cooling fins.
Large dimensions: the AMG high-performance composite braking system
The AMG high-performance composite brake system is adapted to the enhanced performance of the AMG GT S Roadster. The front axle features composite brake discs measuring 390 x 36 mm with 6-piston fixed callipers, with composite brake discs measuring 360 x 26 mm and single-piston fixed callipers at the rear. The brake callipers are painted in red with “AMG” lettering.
There is also the option of the AMG high-performance ceramic composite braking system with brake discs in size 402 x 39 mm at the front axle and 360 x 32 mm at the rear, together with specially painted brake callipers with “AMG Carbon Ceramic” lettering. Exceptionally short stopping distances, a precise pressure point and outstanding resistance to fading even under extreme operating conditions – the AMG high-performance ceramic composite braking system offers motorsport-like braking performance and weighs around 40 percent less than with conventional composite brake discs.
Intelligent lightweight construction with high proportion of aluminium
For the body of the GT S, Mercedes-AMG has opted for an intelligent and particularly lightweight mix of materials with a high proportion of aluminium. The spaceframe and exterior parts are of aluminium, and the boot lid too is particularly light in weight thanks to an innovative composite material. The load-bearing structure is of SMC (Sheet Moulding Compound). These high-tech plastics excel with their lightweight design, high strength and outstanding surface quality. The innovative materials were developed by the Mercedes-Benz TEC factory in Sindelfingen, and brought to production maturity together with the AMG specialists in Affalterbach. The extremely lightweight front deck made of magnesium reduces the inertia ahead of the front axle, improving the agility of the Roadster.
Weight-optimised: the fabric soft top
The three-layered fabric soft top is supported by a magnesium/steel/aluminium structure of low weight, which helps to keep the vehicle’s centre of gravity low. Additional roll-over protection is provided by an integrated aluminium cross-member, while the inserted acoustic mat improves noise comfort.
Authentic sports car experience embodying sensual purity
From the expressive AMG radiator grille to the long bonnet and the muscular tail end, the two-seater guarantees a pure sports car experience even when stationary. The flat front section and forward-sloping radiator grille make the Roadster appear to hug 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 front apron in jet wing design emphasises the car’s width, making it sit flatter on the road. The large outer air inlets guarantee the supply of cooling air to the engine. The LED High Performance headlamps offer more safety at night and an unmistakably sporty and distinctive look. Thanks to LED technology, they illuminate the road more effectively than conventional headlamps – with lower energy consumption.
Viewed from the side, the arched roof line (when the soft top is closed) and the frameless doors are eye-catching features. The surfaces and lines of the side wall flow into the tail end with a dramatic tapered effect. The long bonnet with its pronounced powerdomes, the greenhouse which has been moved far back, the large wheels and broad tail end also contribute to the distinctive looks. As standard the AMG GT S Roadster is shod with mixed tyres on 19-inch rims at the front and 20-inch rims at the rear.
AIRPANEL active air management system
The active air regulation system AIRPANEL included as standard is a particular technical highlight. Vertical louvres at the bottom of the front apron are opened and closed electronically by means of an electric motor in around one second to guarantee the required amount of cooling. Constantly achieving the ideal position calls for highly intelligent and fast control.
During normal driving with no increased cooling demand, the louvres are closed for reduced drag and the air is directed at the underbody. This improves the aerodynamic efficiency of the vehicles. Only when certain components reach predefined temperatures and the air demand is particularly high do the louvres open to allow the maximum cooling air flow to the heat exchangers.
As another active aerodynamic component the Roadster features an extendable rear spoiler. This reduces lift at the rear axle at higher speeds. With its broad shoulders and expressive tail light graphics, the rear end enhances the emotional overall appearance.