EngineTwin-Turbo 4.0L V-8
Power469 / 503 HP, 479 / 516 LB-FT
Few crossovers can effectively maximize passing zones like the AMG-fettled GLC, and its blistering acceleration is in another world compared to the response of the typical crossovers that fill our nation's freeways and parking lots. So, too, is the two-mode soundtrack that's muscular without being obnoxious. Whereas the standard 2020 GLC 300 is powered by a 255-hp 2.0-liter turbo-four and the step-up GLC 43 uses a twin-turbo V6, AMG stuffs a V8 with twin turbochargers into the GLC 63.
The 4.0-liter biturbo V8's output does not increase for 2020, not that it needed to. The hand-built engine makes 469 horsepower at 5,500 rpm and 479 lb-ft of torque at 1,750 rpm. That is unless you spring for the "S" version of the GLC 63 Coupe, in which case 503 ponies and 516 lb-ft are on hand. (The only other V8 found in a compact crossover is in the Jaguar F-Pace SVR, which gets 550 horses and 502 lb-ft from its supercharged V8.) AMG estimates the 0-to-60-mph time at 3.8 seconds for the standard GLC 63 models and 3.6 for the GLC 63 S Coupe. The S Coupe also has a 174-mph top speed, versus 155 mph for the non-S models.
Getting a tall-bodied crossover to hustle like a high-end sports sedan is no easy feat, and doing so requires a major assist from technology. The 2020 version gets even more help, including standard air-spring suspension, adaptive damping, 4Matic+ all-wheel drive, and, new for 2020, an electronically controlled locking rear differential that apportions torque side to side across the rear axle.
The programming to optimize all that hardware is largely contained within the selectable drive modes, which now control even more aspects of the GLC 63's mechanicals. The previous GLC drive modes of Slippery, Comfort (the default), Sport, Sport+, and Race (S model only) return, and they continue to alter damping, steering, throttle mapping, transmission behavior, and exhaust note.
But they're now supplemented by four AMG Dynamics modes. These aren't user-selectable; rather, they're paired to some of the drive modes. The AMG Dynamics modes alter stability control programming, engine mount stiffness (in the S model), the electronically controlled rear differential lock, and the 4Matic+ front-to-rear torque distribution. Slippery and Comfort drive modes utilize the least aggressive AMG Dynamics mode, "Basic". "Advanced" goes with the Sport drive mode, and "Pro" is assigned to the Sport+ mode. In the S model, "Pro" is also assigned to the Race drive mode, unless you take the additional step of switching off the stability control system which activates the "Master" dynamic mode.
To make things even more confusing, some of the systems affected by the set AMG Dynamics modes can also be altered individually by the user without changing the drive mode, using dedicated buttons on the console. The S model also gets AMG drive unit buttons on the steering wheel, two of which are configurable.
With the aid of all these features, the GLC 63 S was able to claim the mantle of fastest SUV on the Nürburgring, with a lap time of 7 minutes and 49 seconds, toppling the Alfa Romeo Stelvio Quadrifoglio and its time of 7 minutes 51 seconds. Should you want to tackle the 'Ring — or one of several other racetracks — yourself, the GLC 63's Track Pace program can show circuit layouts and braking points in the available head-up display, and can record your heroic track times.
We didn't drive the GLC 63 S Coupe on a track, but even on the road, handling is exceptional for this class of vehicle. Turn-in is amazing given the relatively high center of gravity, cornering is flat, and the steering is direct.
But as is often the case with SUVs turned into ultra-high-performance machines, there's a price to be paid. That price — besides the one on the window sticker, which we'll get to later — is an ultra-stiff ride, even in the default Comfort mode. Additionally, the ultra-wide tires begin crabbing when the steering wheel is turned full lock, and the AMG-tuned nine-speed, which uses a wet clutch rather than a torque converter, isn't always smooth when maneuvering at low speeds.
The sportified interior is not compromised in its livability — unless you're talking about the Coupe's marginal rear headroom, less-spacious cargo hold, and reduced visibility. The optional AMG Performance high-backed bucket seats aren't nearly confining as the chairs in the Stelvio Quadrifoglio, and should be fine for most drivers.
Elsewhere inside, the 2020 GLC 63 gets the same updates as the rest of the GLC lineup, with the biggest being the new MBUX infotainment interface. The central display screen now measures 10.25 inches, can show up to three functions at once, and uses artificial intelligence to respond to voice queries prefaced by, "Hey, Mercedes." The system can also respond to certain gestures when optioned with the MBUX Interior Assistant. The navigation system can now place directional arrow overlays on a feed from the front camera, a useful innovation. There's also a new standard digital instrument cluster. And the new steering wheel includes mini touchpads that respond to vertical or horizontal swipes, controlling aspects of two forward screens.
Outside, the GLC 63s are denoted by their grille opening, which widens toward the bottom, and which is filled with a set of vertical bars. The lower fascia, lower bodyside extensions, wheel-arch moldings, rear bumpers, and wheels as large as 21 inches further distinguish these AMGs from lesser GLCs, and the design has been slightly tweaked.
The 2020 versions of these AMG-maximized crossovers will rumble into dealerships in late 2019. The GLC 63 4Matic SUV starts at $74,745. The fastback GLC 63 Coupe, with a starting price of $77,495, commands a $2,750 premium over its more practically shaped counterpart. At the top of the heap, the baller GLC 63 S Coupe is $7,600 more than the non-S version at $85,095. (All prices include $995 destination.) The Coupe variant hinders rear visibility, slashes cargo space, but it's the only way to get the "S" version, so for those seeking the max-attack GLC, it's the way to go. After all, practicality is for lesser GLCs; the GLC 63 is all about making a statement.