The worst part about the 2020 Mercedes-AMG GLC 63 S is that it’s exclusive to the Coupe. Want the practicality of the standard GLC body style with the 503-bhp twin-turbocharged 4.0-litre V8 engine from the S model? Tough luck, because Mercedes-AMG limits the upright GLC 63 to the standard 469-bhp engine. Of course, Mercedes also offers the Coupe sans S, but if you’re not prepared to go big, then you might as well go home.

At £77,089, the GLC 63 S Coupe stickers for £6,750 more than the entry-level GLC 63 Coupe. Alongside its additional 34 horses, the S model pumps peak torque up from 479 pound-feet to 516 and adds adaptive engine mounts to improve noise, vibration, and harshness.

The extra grunt of the S cuts the sprint to 60 miles per hour to 3.6 seconds from the base GLC 63’s 3.8-second run, while the top speed rises to an electronically limited 174 mph from the standard model’s figure of 155 mph. S or not, the GLC 63 is quick. Damn quick. In fact, the BMW X3 and X4 M Competition, Jaguar F-Pace SVR, Land Rover Range Rover Velar SV Autobiography Dynamic, and Porsche Macan Turbo all need more than four seconds to hit the mile-a-minute mark from a standstill, while the GLC 63 S ties the Alfa Romeo Stelvio Quadrifoglio for quickest in class.

2020 Mercedes-AMG GLC 63 Coupe: First Drive
2020 Mercedes-AMG GLC 63 Coupe: First Drive

Land Yacht

Predictably, the GLC 63 S Coupe proves an absolute riot on the wet roads that snake through New York’s Dutchess County. Riding on a set of optional 21-inch wheels (20s are standard), the 2,063 kilogram crossover’s Pirelli P Zero summer rubber struggles to stick to the wet tarmac. Boot the accelerator pedal and the tyres momentarily lose grip as the all-wheel-drive system seamlessly shifts power between the front and rear axles (it sends up to 100 percent of the engine’s grunt rearward or 50 percent forward). Enter turns with a bit too much fervour and understeer sets in. It’s all good fun, though, and if anything goes amiss, the big 390-mm front and 360-mm rear brake discs work with a firm pedal to bring the 2,063-kg crossover to a drama-free halt.

Likewise, the nine-speed automatic transmission amuses with its quick shifts and the accompanying staccato blats that emit from the active exhaust system’s pipes. Even in Comfort mode, the gearbox, which uses a wet clutch in place of a torque converter, behaves prophetically; it ably holds gears through turns and swiftly kicks down a few cogs following a prod of the right pedal.

Predictably, the GLC 63 S Coupe proves an absolute riot on the wet roads that snake through New York’s Dutchess County.

Switch to Sport, Sport Plus, or – the S-exclusive – Race driving modes (there’s also a Slippery mode, as well as a configurable Individual setting), and the powertrain’s responsiveness improves, the heavy but direct variable-ratio steering gets even weightier, and the air suspension’s already rigid ride gets even firmer. Swapping drive modes also adjusts the distribution of torque between the front and rear wheels, the thresholds of the stability control system, and the parameters of the electronically controlled locking-rear differential.

Frankly, the configurability of the AMG GLC is a bit overwhelming, although the addition of a drive mode dial to the leather and faux-suede steering wheel of the S model at least makes it easier to alter the crossover’s dynamic settings on the fly. The feature is an option on the lesser GLC 63 and also shares space on the thick-rimmed wheel with a pair of chunky paddle shifters, as well as the likes of the infotainment and cruise controls.

2020 Mercedes-AMG GLC 63 Coupe: First Drive

Premium Blend

Like the GLC 300, the GLC 63 welcomes the Mercedes-Benz User Experience (MBUX) infotainment system into its fold. The setup relies on a dashboard-mounted 10.3-inch touchscreen with an associated console-mounted touchpad, as well as a finicky set of touch-sensitive steering wheel controls that also interact with the 12.3-inch digital gauge cluster.

More enterprising users can navigate the system via the voice recognition system, which activates with the push of a steering wheel button or by saying the phrase, “Hey Mercedes.” The latter function, however, falls prey to false queries and often responds to the mere mention of the word “Mercedes.”

Like the GLC 300, the GLC 63 welcomes the Mercedes-Benz User Experience (MBUX) infotainment system into its fold.

Yet, the oversensitivity of MBUX’s voice recognition function is no more maddening than the raucous thrum from the available 21-inch Pirelli tyres or the uncomfortably tall lift-over height and small cargo hold of the Coupe. With a maximum of 1,399 litres of space, the Coupe’s hatch is down 201 litres to the upright GLC 63.

What the GLC 63 Coupe lacks in cargo room, it makes up for with its tastefully tapered roofline and model-specific S trim. Thanks to an exterior refresh that includes new headlights, a larger grille, and revised taillights, the 2020 Mercedes-AMG GLC 63 S Coupe’s looks toe the line between elegance and menace with more grace than ever before. If only the most powerful variant of AMG’s compact crossover offered a bit more versatility, as well.

2020 Mercedes-AMG GLC 63 S

Engine Twin-Turbocharged 4.0-Litre V8
Output 503 bhp / 516 Pound-Feet
Transmission Nine-Speed Automatic
Drive Type All-Wheel Drive
Speed 0-60 MPH 3.6 Seconds
Maximum speed 174 MPH (Electronically Limited)
Efficiency 16 City / 22 Highway / 18 Combined
Weight 2,063 kilograms
Seating Capacity 5
Cargo Volume 201 / 1,399 litres
Base Price £71,410
As-Tested Price £78,160