Standing in the paddock of Miami's new Concours Club circuit in June means having to endure temperatures of nearly 100 degrees (38 C). But it's not the heat that will kill you – it's the 90 percent humidity. The only thing keeping me from going totally insane is the stream of free Fiji water and the fact that soon I'd be in the driver's seat of a certified German supercar: the 2021 Mercedes-AMG GT Black Series.

Lurking under the bonnet of the GT Black Series is 720 bhp courtesy of a twin-turbocharged, flat-plane-crank 4.0-litre V8. This car will hit 60 in 3.1 seconds on its way to a top track speed of 202 miles per hour. And if you needed any other evidence as to how fast the Black Series is, it's the second-quickest production car around the Nurburgring with a lap time of 6:43.6. Only the Manthey-accessorised Porsche 911 GT2 RS does it quicker.

But only overzealous automotive nerds care about Nurburgring lap times, anyways. What really matters is that the GT Black Series is the most bonkers street-legal track weapon that Mercedes-AMG has ever built. It’s a shrine to all Black Series models before it, and the quickest, most powerful thing to come from Affalterbach. And it only takes one look to recognise how absurd it is.

2021 Mercedes-AMG GT Black Series Exterior
2021 Mercedes-AMG GT Black Series Exterior

Wings And Other Things

The GT Black Series pictured here is one of just two in the US at the moment; even Mercedes-Benz USA has a tough time getting its hands on these things since they are so exceptionally rare (and completely sold out). This one wears an eye-searing shade of Magmabeam Orange, while the other Black Series is a subtler – but also handsomer – car that wears Brilliant Blue Magno.

Both models get an aggressive two-stage splitter on the front end, a new vented bonnet, custom wheels, and a wing on top of a wing on top of a wing (spoiler, technically) that helps return a remarkable 882 pounds of downforce at 155 miles per hour – not even the GT2 RS has that much. Only in a special “Master” mode does the wing fully extend for maximum downforce, but more importantly, it just makes the GT Black Series look absolutely sinister.

All that additional carbon reduces the Black Series’s weight by around 35 kg (77 pounds) compared to the next-best AMG GT R.

Just behind the front wing/fender sits a new carbon fibre vent that sends fresh air up and over the wheel wells for additional downforce and into the brakes for extra cooling. Extended underbody panelling with longitudinal fins helps direct air out the rear, and even something you don't see – the radiator – slopes downward behind the grille to improve cooling and reduce drag. All that additional carbon reduces the Black Series’s weight by around 35 kg (77 pounds) compared to the next-best AMG GT R.

The inside of the GT Black Series is entirely familiar but still likeable. The carryover 10.3-inch central screen and its MBUX software offer Android Auto and Apple CarPlay connectivity, while the 12.3-inch cluster is familiar from other products, too. There are exclusive Black Series touches, like orange contrast stitching, a full Dinamica dash and steering wheel, and lightweight door panels with loop straps instead of conventional handles. But the overall experience is essentially the same as the base GT, and that's not a complaint.

2021 Mercedes-AMG GT Black Series Interior
2021 Mercedes-AMG GT Black Series Interior
2021 Mercedes-AMG GT Black Series Interior
2021 Mercedes-AMG GT Black Series Interior

Slinking into the bucket seats, even with a helmet, doesn't require turning your limbs into pretzel pieces. The cabin is comfortable, and yet the seating position is pretty much perfect for high-performance driving – some supercars require you to sacrifice one for the other. You don’t get the optional carbon buckets or six-point harness in the US (that’s only for Europe), but I had no complaints with the standard leather seats, they were well-bolstered and comfortable enough.

The exceptionally long bonnet and short windscreen aside (same issues I have with the base GT), the Black Series very much feels like a car that you can drive daily. I never got a chance to test that theory though, because Mercedes only wanted me to experience the GT Black Series in its natural habitat: on the track.

2021 Mercedes-AMG GT Black Series Exterior
2021 Mercedes-AMG GT Black Series Exterior
2021 Mercedes-AMG GT Black Series Exterior Details

Track In Black

The Concours Club is no Nurburgring, with the tight, twisty, 2.0-mile circuit's front and back straights offering the only real chances to let the GT Black Series's 720 horses run free. I attack both at the first opportunity, laying the throttle to the floorboard and allowing that flat-plane crank V8 to do its thing.

Mercedes-AMG smartly transitioned from a traditional cross-plane layout in the base GT to a flat-plane setup here. Although the redline only jumps by about 200 rpm, the throttle response is noticeably quicker, the powerband is more linear, and with two turbos producing 24.6 pounds of boost, there isn't an inkling of hesitation. Add to that a seven-speed dual-clutch transmission that accompanies each rapid-fire shift with impressive recoil, and you have yourself a potent combination.

The carbon-ceramic stoppers are super grippy and yet easy to modulate with a quick catch point.

The GT Black Series easily touches 125 miles per hour down the long back straight before I have to get on the brakes, and that's only about a quarter of what this car can actually do. Under my right foot I can feel how much power is still available and wanting to be unleashed, even at these speeds. The only thing keeping the Black Series from breezing to 200 miles per hour and beyond is the lack of asphalt.

As the back straight turns into a tight right-hander, I stand on the brake pedal half-expecting the Black Series to drop its nose, wiggle its butt, and slow just enough for me to toss it in. But there are no dramatics nor wiggling – the GT stays straight as an arrow as it slows from 125 mph to something more manageable. The carbon-ceramic stoppers are super grippy and yet easy to modulate with a quick catch point. And even after 15 or so laps, there was barely any evidence of fade, thanks in no small part to new wing/fender vents that send more air to the discs. The GT Black Series has some of the best brakes I've ever tested.

With perfect 50/50 weight distribution thanks to the front-mid engine placement and the rear-mounted transaxles, the GT Black Series slithers its way through the blind turns on the rearmost portion of the track gracefully. The steering is perfectly weighted (although it's not super chatty), the nose tucks into corners aggressively, and the Michelin Pilot Sport Cup 2 R tyres offer unyielding levels of grip. All of this makes the Black Series feel completely effortless to pedal quickly.

Would alternatives like the GT2 RS or McLaren 765LT move a bit better? Most likely, and probably with more personality too. For as fast and ferocious as it is, the GT Black Series is a bit clinical by comparison, which almost feels blasphemous to say about a 720-bhp supercar. But that's not to suggest that the Merc isn't still ridiculously fun in its own right – turning perfect laps can be as just enjoyable as going sideways, and the GT Black Series does that exceptionally well.

2021 Mercedes-AMG GT Black Series Exterior

The Ultimate AMG

The Mercedes-AMG GT Black Series costs $325,000 in the US, (£335,000 in the UK) which is a lot. Even the sporty AMG GT R is only $165,000 by comparison, and it definitely doesn't feel $160,000 worse. But don't worry, you won't be able to get your hands on a new GT Black Series anyways since it's completely sold out. And to put salt on the wound, this is the last fast GT we'll see before the range drives off into the sunset.

Those lucky (read: wealthy) enough to already have a GT Black Series on order get a track weapon in the truest sense. This is the fastest, most powerful, and sharpest AMG product to date, as evidenced by its impressive Nurburgring lap time. But even with 720 horses and enough wings to make a fighter jet blush, the Black Series is as tractable as it is trackable, and that’s what makes it so appealing.

AMG GT Black Competitor Reviews:

Gallery: 2021 Mercedes-AMG GT Black Series

2021 Mercedes-AMG GT Black Series

Engine Twin-Turbocharged 4.0-liter V8
Output 720 Horsepower / 590 Pound-Feet
Transmission Seven-Speed Dual-Clutch
Drive Type Rear-Wheel Drive
Speed 0-60 MPH 3.2 Seconds
Maximum speed 202 MPH
Efficiency 15 City / 20 Highway / 17 Combined
Weight 3,500 Pounds (est)
Seating Capacity 2
Base Price $325,000