In the standard GLE63 Coupé, it delivers 549bhp at 5750rpm and 516lb ft on a band of revs between 1750 and 5500rpm.
For the range-topping GLE63 S Coupé, the engine musters an additional 28bhp and 44lb ft thanks to increases boost pressure and other internal tweaks to offer a stout 577bhp at 5500rpm and 560lb ft between 1750 and 5250rpm.
By comparison, the new BMW X6 M’s twin-turbocharged 4.4-litre V8 produces 564bhp and 553lb ft, while the twin-turbocharged 4.8-litre V8 used by the new Porsche Cayenne Turbo S provides 562bhp and 590lb ft.
The GLE63 Coupé’s heady reserves are channelled permanently to all four wheels via AMG’s seven-speed 7G-Tronic SpeedShift Plus automatic gearbox and a specially tuned version of Mercedes-Benz’s 4Matic four-wheel drive system that has been set up to provide a nominal 40 per cent front, 60 per cent rear apportioning of drive.
Official performance figures made public at its unveiling suggest the latest AMG model will offer straight-line acceleration consummate with the high-riding performance SUV competition, with the standard GLE63 Coupé possessing a claimed 0-62mph time of 4.3sec and the more powerful GLE63 S Coupé running an even sharper 4.2sec. This compares to the BMW X6 M and Porsche Cayenne Turbo S’s claimed 0-62mph times of 4.2sec and 4.1sec respectively.
The top speed for both GLE63 Coupé models is limited to 155mph, while their combined fuel consumption is put at 23.7mpg, along with average CO2 emissions of 279g/km.
The GLE63 Coupé rides on a sophisticated chassis adapted from the existing ML63 AMG, itself due to be facelifted and renamed as the GLE63 in line with Mercedes-Benz’s new naming system in 2015.
It uses a specially tuned version of the German car maker’s AirMatic air suspension sey-up with variable damping control and self-levelling properties, a so-called Active Curve system employing hydraulic motors on the stabiliser bars to provide added body control and greater cornering speeds than regular GLE models.
The GLE63 Coupé comes with 21-inch wheels shod with 285/45 profile front and substantial 325/40 profile rear tyres, while the GLE63 S Coupé receives larger 22-inch rims.
The steering, meanwhile, is a modified version of the standard GLE Coupé’s electro-mechanical Direct Steer system. Tuned specifically by AMG for the GLE63 Coupé, it receives speed-dependent variable-ratio assistance and unique mapping.
The new performance SUV also offers five different driving modes: Comfort, Sport, Sport Plus, Individual and Slippery Transmission, the latter of which has been developed to provide what AMG describes as “optimum traction and maximum driving stability in adverse road conditions”.
Helping to rein in the new AMG model’s substantial performance is an upgraded braking system consisting of vented and cross-drilled 390mm front and 345mm rear steel discs.
The GLE63 Coupé is distinguished from lesser GLE Coupé models by a series of typical AMG exterior styling cues that serve to provide it with an added touch of visual aggression.
Included is a heavily structured front bumper featuring the Mercedes-Benz performance car division’s latest two-tone A-wing design, a twin-blade grille, standard LED headlights, twin-dome bonnet, more substantial cladding within the wheel arches, a lip spoiler attached to the tailing edge of the tailgate and a rear bumper incorporating diffuser fins and twin chromed tailpipes.
Reflecting its added performance potential, the GLE63 S Coupé sports a uniquely coloured front bumper with black elements, along with titanium grey alloy wheels.
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