Mercedes-AMG unleashes GT R

MERCEDES-AMG has uncovered its new sports flagship, the GT R coupe, which is said to pack in more motorsport technology than any production vehicle to have ever emerged from the high-performance partnership.

Expected to arrive in Australia in July next year, the GT R raises the bar that was set incredibly high with the current GT S – priced from $294,610 before on-road costs in Australia – with considerably more power, improved performance and even sharper dynamics for the two-seat rear-drive super-sports coupe.

The mid-front-mounted dry-sump 4.0-litre twin-turbocharged V8 engine has undergone major surgery – new turbos with modified compressor machining and extra boost pressure (up from 1.2 to 1.35 bar) headline a host of modifications – to produce an extra 55kW of power and now peaks at 430kW (at the same 6250rpm).

Maximum torque remains at 700Nm, although the pulling power peak period now stretches from 1900rpm to 5500rpm compared to the narrower 1750-4750rpm bandwidth on the GT S.

Benefiting further from improved aerodynamics and lighter components that see 15kg shed from the kerb weight of the GT S, the 1630kg R machine sends all that mumbo to the tarmac via a suitably revised seven-speed DCT Speedshift dual-clutch automatic transaxle and standard limited-slip differential.

The GT R is able to accelerate from 0-100km/h two-tenths quicker at 3.6 seconds and power on to a new electronically limited top speed of 318km/h, up 8km/h on the GT S.

Lightweight carbon-fibre is used in areas such as the front wings, roof and a “torque tube” – nestled between the engine and transmission with a newly developed “tunnel cross” component mounted underneath – along with a specially developed carbon-fibre exhaust to not only reduce weight but increase the coupe’s torsional rigidity by a claimed 7.5 per cent.

As well as extensive use of aluminium and other weight-saving materials across the vehicle, there are fewer sound-deadening materials and a new optional set of lightweight AMG Performance forged alloy wheels – 19-inch at the front and 20-inch at the rear, in a 10-spoke matt-black design.

The work of the aerodynamicists becomes apparent when looking beyond the broad, toothy “Panamericana” grille – a nod to the GT3 racing car and a tribute of sorts to the 300 SL that won the Panamericana road race in Mexico in 1952 – and the “Green Hell” paintwork – named in honour of the northern loop of the Nurburgring racetrack on which the GT S was developed.

There is a carefully crafted new front fascia, large rear aerofoil and new rear fascia with double diffuser, for example, along with a new underbody component that automatically moves downward by about 40mm when “race” mode is selected via the transmission’s “dynamic select controller” and vehicle speed hits 80km/h.

Mercedes-AMG says the resultant venturi effect can reduce front axle lift by around 40kg at 250km/h, while all the aerodynamic measures combined increase the surface contact at top speed by 155kg compared with the regular AMG GT.

Technical highlights beyond those already on the GT S just keep on coming with the R-rated version, with other new features including active rear-wheel steering, a nine-way adjustable traction control system and adjustable coil-over suspension with additional electronic control.

The suspension remains a double-wishbone design front and back, but the rear axle now has heavier-duty uniball bearings on the lower wishbones and employs a thicker anti-roll bar.

The driver can now adjust the suspension spring pre-load manually, changing the drive and roll behaviour as well as the grip levels, Mercedes says, to tailor them to personal preferences or to a particular racetrack.

This combines with the AMG Ride Control adaptive damping system, which is electronically controlled and automatically adapts the damping on each wheel, with the driver offered a degree of adjustment via three different modes.

The electro-mechanical rear-wheel steering marks the first application for this type of system on a Mercedes-AMG model, bringing with it a claim from the manufacturer of an “ideal combination of agility and stability – handling characteristics that are normally in direct conflict”.

The new traction control system, meanwhile, allows the driver to pre-select the amount of slip tolerance at the rear axle – in nine predefined levels – via a rotary switch on the centre console. Level 1 is programmed for driving in wet conditions and thus has “high safety reserves” while Level 9 allows maximum slip.

Further improving the dynamic performance of the GT R, the Affalterbach-based technical team has seen fit to widen the front and rear track while the 19-inch front and new 20-inch rear wheel and tyre combination is fitted standard with Z-rated Michelin Pilot Sport Cup 2 tyres measuring 275/35-section at the front and 325/30 at the rear.

Various body and chassis reinforcements have also been made, while the front/rear weight distribution remains 47:53.

The high-performance braking package appears to be the same – with standard 390mm front/360mm rear brake rotor diameters – although the callipers are painted yellow instead of red on the GT S.

Mercedes-AMG chief executive Tobias Moers revealed to GoAuto at the New York motor show in March that the GT R would be even faster on the racetrack than the C63 AMG Black Series and would easily match – if not surpass – the performance of the heralded SLS AMG Black Edition.

In announcing the full details of the GT R today, he said the company had now “reached the next level of driving performance”.

“This road-going sportscar with motor racing genes and innovative technical solutions offers an ultimate driving experience that allows people to feel our motorsport origins in every fibre,” he said.

“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.”