Mercedes-Benz SL-Class vs Mercedes-Benz GT

What's the difference?

The new Mercedes-AMG SL63 4Matic+ is guaranteed to turn heads for decades to come. But there’s enormous design and engineering substance underpinning this car’s undoubted good looks. Stunning performance, superb dynamics and top-shelf safety make this a powerhouse GT to be reckoned with.

Note: CarsGuide attended this event as a guest of the manufacturer, with accommodation and meals provided.

The Mercedes-AMG GT Black Series is a rare beast; in the sense that it’s both unattainable and that it makes you feel like a superhero behind the wheel.

There is more performance on offer than most can hope of using, but the best thing about Mercedes’ latest supercar is its approachability.

In my experience, the more expensive a car gets, the more stressful driving them becomes, but the Mercedes-AMG GT Black Series does something I didn’t think was possible, and turns a near-$1 million supercar into something fun.

Rather than a strict two-seater, this time around the SL adds the flexibility of ‘+2’ rear seating while the previous 'Vario’ folding hardtop has been binned, the new car returning to a traditional, electrically-folding and weight-saving (-21kg) soft top. 

Mercedes-Benz design chief Gorden Wagener started the new model’s development from a ‘clean sheet’ and Mercedes-AMG says “not a single component comes from the predecessor SL, or any other model such as the AMG GT Roadsters”. 

Always a subjective call, but I think this car’s proportions are just about perfect. The lengthy bonnet with its twin longitudinal ‘Power Domes’, raked windscreen and fat haunches create a wide stance and presence that’s almost impossible to ignore.

Aggression, as with the sinister headlights and 21-inch rims, is subtly combined with soft curves along the flanks and around the rear. Note the seamless door handles.

And it’s not all about aesthetics. Active aero has been integrated into the front apron and retractable rear spoiler. Plus the ‘Z-fold’ roof design does away with the need for a separate cover.

The interior is sub-zero cool with slick screens, an 11.9-inch display covering multimedia and a 12.3-inch unit for instrumentation ahead of the driver, being particular highlights.

Turbine-style air-vents at the leading edge of the split-level dash and alloy trim elements are a tip-of-the-hat to SLs past and the deft mix of large flat surfaces with complex curves oozes design confidence.

Most high-performance brands have their hardcore, track-focused models, from the Porsche 911 GT2 RS to the McLaren 765LT and the Ferrari 488 Pista.

For Mercedes-Benz, it’s the Black Series, a badge which could be found in the past on the SLK, CLK, SL-Class, C-Class, but for 2021 it’s now found on the back of the GT supercar.

To differentiate it from the rest of the ‘standard’ Mercedes-AMG GT range, a slew of racecar-like components are added, such as a fixed rear wing (with deployable insert), vented front fenders, extended front splitter and fixed-back seats.

In fact, so different is the Black Series, that the only panel that carries over from the GT is the roof, which is a carbon-fibre component to keep weight down.

Other carbon-fibre bits include the front fenders, front and rear bumpers, and rear hatch.

The most in-your-face addition might be the deeply vented bonnet, designed to evacuate hot air from the engine bay, while the hero 'Magma Beam' orange colour that juxtaposes all the exposed carbon-fibre panels is a real attention grabber.

From the outside, the Mercedes-AMG GT Black Series is bold, brash and in-your-face, but that’s exactly what a race car should be – in my opinion, at least.

I absolutely love how the Black Series looks like a Need for Speed or Forza Horizon video game car brought to life, and will turn heads anywhere you go.

Inside, the Black Series is clad in soft-touch 'Dinamica' and orange contrast stitching across many of the touchpoints such as dashboard, steering wheel and door cards.

And with fixed-back bucket seats, a racing harness and a roll cage, you’d be forgiven for thinking the AMG GT Black Series is all about function over form, but there are small touches to make it easier to live with on the road.

The multimedia touchpad controller falls easily in hand, while the shifter is flanked by an array of light-up buttons to adjust settings like adaptive suspension, exhaust note and rear spoiler angle.

Overall, the Black Series’ cabin is well-laid out like a standard AMG GT, with some nice flourishes to stand it apart.

In the context of a high-performance GT, practicality is pretty impressive.

At just over 4.7m long the SL is a sizeable machine and much of its lengthy (2700mm) wheelbase is devoted to making the driver and front passenger comfortable.

There’s plenty of space for that pairing and just enough storage to cope with the ‘things’ they’ll typically bring with them.

Door pockets offer enough room for a few odds and ends, although you’ll struggle with even a medium-size bottle unless you’re willing to lay it down horizontally along the top of the aperture.

A handy lidded bin between the front seats doubles as a centre armrest, there are two cupholders under a sliding lid in the centre console and the glove box is a decent size. 

Power and connectivity options run to four USB-C ports, a 12-volt socket and the wireless device charging pad.

Then there are the rear ‘+2’ seats, and Mercedes makes no bones about the fact they’re intended for occasional use only, even suggesting a 1.5m occupant height limit.

And there’s no doubt they offer a handy emergency seat or a fun kids’ zone. Just ask a Porsche 911 Carrera owner how much this kind of seating arrangement increases a sports car’s flexibility.

At 183cm I gave the back seat a crack, which meant sliding the front (passenger) seat way forward with the backrest close to upright. But I squeezed in, and there was just enough legroom for a person in front at the same time. 

With the roof in place there’s the added pleasure of cranking your head over to around 45 degrees. But it’s do-able! 

No storage, adjustable ventilation, or power back there. But that’s fair enough, especially given there are USBs available in the front centre storage box.

Boot volume is 240 litres with the roof up and 213 litres with it folded, which is enough for some light luggage, and not too shabby when you think a Toyota Corolla hatch offers up just 217 litres (with all seats up).

There’s a 12V socket in there, but don’t bother looking for a spare, in the event of a flat your only option is a repair/inflator kit.

As a two-seat coupe, the AMG GT Black Series isn’t the most practical of cars, but then again, it isn’t trying to be.

The cabin is big enough to accommodate six-foot tall (183cm) passengers like myself, though the fixed-back seats are designed to be form-fitting even for slender frames.

Storage options inside include two cupholders and a shallow underarm storage cubby, and that’s about it.

Unlike the standard GT, the Black Series’ doors forgo the small storage pocket – likely to keep weight down.

Opening the boot reveals enough space for a set of golf clubs or a few weekend bags, but not much else.

Mercedes does not list the volume available in the Black Series, but with the inclusion of a rollcage and special reinforcement components to help transfer the downforce of the rear wing to the chassis, it’s safe to assume it is less than the 176 litres offered in the AMG GT.

Wearing a price tag of $796,777, before on-road costs, the Mercedes-AMG GT Black Series costs more than double the $373,276 GT R coupe, and an eye-watering $343,577 more than last year’s limited-release GT R Pro.

It’s a significant amount of cash for sure (still not enough to buy a decent house in Melbourne’s inner city, though), but, as well as increased performance, you are paying for exclusivity.

The GT is only the sixth model in Mercedes’ long history to wear the Black Series badge, and production of the new model will be limited, though to what extent is currently unclear.

Only 28 units will make it Down Under though, and each is already spoken for.

Weirdly, this makes last year’s GT R Pro rarer with only 15 examples in Australia, while the SLS Black Series was also more exclusive with only seven available locally.

So, what exactly do you get for your extra spend?

Remarkably, the equipment list on the Black Series largely mirrors its GT siblings, including a flat-bottom steering wheel, staggered 19-/20-inch wheels, push-button start, 12.3-inch customisable digital instrument cluster, dual-zone climate control and various driving modes.

Handling multimedia duties is a 10.3-inch multimedia screen with satellite navigation, Apple CarPlay/Android Auto connectivity, digital radio and an 11-speaker sound system.

However, the Black Series adds a few more touches to the cabin to make things feel more special, such as a microfibre-clad steering wheel, fixed-back carbon-fibre seats, orange-stitch detailing, a roll cage and a four-point racing harness.

Though that doesn’t sound like it's enough to justify the huge step up from the GT R, as is the case with most special-edition models, the engine and mechanicals have been given a thorough workover to extract maximum performance from the platform (more on this below).

This new ‘4Matic’ all-wheel-drive SL63 features AMG’s (M177) 4.0-litre twin-turbo V8, superseding the previous rear-wheel-drive SL’s similarly configured 5.5-litre unit.

Hand built by one AMG technician from start to finish, it produces 430kW (around 580hp) from 5500-6500rpm and 800Nm across a broad plateau from 2500-5000rpm.

It’s something of a mechanical masterpiece, and the previous seven-speed auto transmission, driving the rear wheels only, has been replaced by a nine-speed dual-clutch auto (with wet multi-disc start-off clutch) sending drive to all four wheels via Merc’s ‘4Matic’ AWD system.

Powering the GT Black Series is AMG’s ubiquitous 4.0-litre twin-turbo-petrol V8 engine, with a few modifications.

For starters, a flat-plane crank is used for the V8 for improved throttle response, less weight and different firing order that makes it more free revving than the standard engine.

In fact, so different is the engine that Mercedes-AMG has given the Black Series’ powerplant its own internal code, with only three technicians in Affalterbach qualified to put it together.

The result is peak power of 537kW available from 6700-6900rpm, while maximum torque reaches 800Nm, on tap from 2000-6000rpm.

For those keeping track, that’s 107kW/100Nm more than the GT R.

Sending drive exclusively to the rear wheels via a seven-speed dual-clutch automatic transmission, the AMG GT Black Series will accelerate from 0-100km/h in just 3.2 seconds and top out at 325km/h.

Mercedes-AMG’s official fuel economy number for the SL63 on the combined (WLTP) cycle is 13.9L/100km, the 4.0-litre twin-turbo V8 emitting 319g/km of CO2 in the process.

On the roughly 300km launch program we covered urban, B-road and some freeway running, returning an (indicated) average of 17.5L/100km. And that reflects some enthusiastic driving along the way.

The fuel tank requires 70 litres of 98 RON premium unleaded to fill it which translates to a theoretical range of around 500km, dropping to 400km using our real-world number.

Officially, the GT Black Series will consume 13.2 litres per 100km, making it thirstier than the GT R that returns 11.4L/100km.

The GT Black Series will require 98RON petrol and this, coupled with the high consumption average, will mean a big bill at the bowser.

However, as such a focused performance machine, fuel economy in the Mercedes-AMG GT Black Series is less of an important point than something like a charismatic and dynamic engine.

I recall driving the AMG SL65 around the backroads of Tassie a few years ago and that twin-turbo V12 monster famously packed 1000Nm of torque, while this car ‘only’ has 800.

But there comes a point where enough is enough… and this is enough!

With maximum torque available from 2500-5000rpm and peak power (430kW) on call from 5500-6500rpm there’s always stupendous acceleration available with a squeeze of your right foot.

Claimed 0-100km/h time is supercar fast at 3.6 seconds, while top speed is a toupe-troubling 315 km/h. And that’s electronically limited!

A typically ferocious engine noise and howling exhaust note accompany rapid progress and shifts from the nine-speed dual-clutch transmission are quick and positive, not to mention especially enjoyable using the steering wheel-mounted paddles.

There are six ‘AMG Dynamic Select’ drive programs from Comfort through to Race, the latter including a Drift Mode, which we didn’t experiment with. Nor did we dip into the ‘AMG Track Pace’ system for circuit-focused mapping and timing

However, far from drifting, the grippy Michelin Pilot Sport 4S rubber (275/35 fr - 305/30 rr) plants the car securely with the all-wheel-drive system and electronic locking rear diff playing their part.

I found the perfect set-up was in the ‘Individual’ mode with the engine, transmission and steering in racier settings and the suspension in ‘Comfort’. The adaptive damping in this configuration mixes smooth ride compliance with sharp dynamic response.

The car’s aluminium space frame chassis is part of a body structure mixing aluminium, magnesium, fibre composites and various strength steels.

Torsional rigidity is claimed to have been improved by 18 per cent and despite the lack of a roof the SL feels tight and solid.

Suspension is by alloy double wishbones front and rear with adaptive damping and active hydraulic anti-roll stabilisation standard (so, no physical anti-roll bars).

At the same time the 4Matic AWD system is able to vary torque distribution up to 100 per cent to the front or rear axle depending on where drive can be put to best use.

The speed sensitive, variable ratio, electronically controlled steering is accurate and turns in beautifully with good road feel. No doubt assisted by electric rear steering able to adjust the angle of the rear tyres by up to 2.5 degrees.

All this adds up to a hugely impressive package that, despite its 1970kg kerb weight, feels agile, athletic and able to attack corners like an overgrown hot hatch, putting its power down with unwavering authority.   

While indecently fast the SL63 can also stop rapidly with the AMG high-performance braking system standard. 

Huge composite ventilated and cross-drilled discs (390mm fr - 360mm rr) are clamped by six-piston fixed alloy calipers at the front and single-piston units at the rear. They wash off speed calmly and consistently with perfect pedal feel.

Even at highway speeds, particularly with the windows up, normal conversation is easy with the roof down. But if you need to raise (or lower) it, the operation takes 15 seconds and is possible up to 60km/h. 

Under the heading of miscellaneous observations, the turning circle is a not insubstantial 12.8m, so beware in the car park.

A front axle lift function is a welcome standard feature, raising the car’s nose 30mm with the press of a button. And lift locations are stored in GPS data, so the car will subsequently remember to lift itself at the same place, even if you don’t! 

Heating and cooling for the front seats combined with the heated steering wheel and Air Scarf neck warming makes winter top-down driving a pleasure.

The digital instrument display is not only crystal clear, it can be changed through multiple configurations, including a tunnel-like graphic for engine revs as well as specific readouts for speed, g-force, the lot.

At the same time, the central media screen’s angle can be adjusted to better cope with reflections and the windscreen wiper system Merc calls ‘Magic Vision Control’ channels fluid along the wiper arms onto the rubbers, which isn’t new, but works spectacularly well here.  

We’ve driven some very fast cars before, so make no mistake when we say the AMG GT Black Series is seriously quick.

The right pedal might as well be warp drive on the, Starship Enterprise, because as soon as you floor the throttle, you’re pinned to the back of the race seat and the only reprise comes from lifting off.

Aside from the immense speed, what is – surprisingly – noticeable is the noise, or lack of it.

The flat-plane crank V8’s different firing order means it doesn’t have the same burbly notes as the standard AMG GT, it’s a racier tone. That’s not a bad thing, mind you, just a different note.

And while the flat-plane crank V8 changes the exhaust note, it also makes the engine freer revving and lively.

With 537kW/800Nm on tap, you sort of have to trust the suspension and aerodynamics will do their thing to keep the AMG GT Black Series on the track, and it’s here where I think Mercedes-AMG has pulled off some sort of magic.

The combination of adaptive dampers, active aero, beefed-up anti-roll bars and a unique Michelin Pilotsport Cup 2 R tyre (featuring a silhouette of the Black Series laser etched into the sidewall) results in a terrifyingly capable vehicle at Phillip Island.

I am the first to admit that I am no Lewis Hamilton behind the wheel, I often get on the throttle too early, I can never nail a double-apex corner and my heel-toe-technique could use more work, but behind the wheel of the GT Black Series, I felt like Ayrton Senna’s spirit had taken the wheel on my behalf.

Cornering in the Black Series felt like nothing else, and regardless of what the speedo was saying, the nose of the ferocious GT flagship would just point wherever I wanted it to go.

Luckily the braking system is also up to task – thanks to carbon ceramic units fitted as standard, as well as unique pads and discs.

The brakes bite almost immediately, giving you the confidence to hit the stop pedal at the last moment before tipping into a corner.

I think the biggest compliment I can pay to the Mercedes-AMG GT Black Series is that it increases that narrow band of fun you can have in a supercar.

Sure, a driver with more skill could pilot the AMG GT Black Series with more grace, and finesse it around the corners a little quicker, but the approachability of the performance on offer is amazing.

Nothing feels intimidating, nothing feels unapproachable. The GT Black Series is so communicative that it gives drivers the confidence to feel like a hero around a race track.

If there is any criticism of the car, it’s that its limits are so high they are hard to explore, even on a circuit like Phillip Island, but maybe that takes more skill than I have, or more than just a handful of laps behind the wheel.

Of particular note, too, is that the engine of the Mercedes-AMG GT Black Series is found in the front.

There’s a reason why some exotic supercars will opt for the mid- or rear-engine layout, but Mercedes has managed to craft a front-engine, rear-drive machine that will keep up with the best the world has to offer.

The 2022 Mercedes-AMG GT Black Series is yet to be assessed by ANCAP or Euro NCAP, and does not wear an official crash-test rating.

Standard safety features do include automatic wipers, automatic high-beam headlights, blind-spot monitoring, adaptive cruise control, driver attention alert, traffic sign recognition and tyre pressure monitoring.

Though the AMG GT Black Series lacks the usual assortment of safety features that you might find on a more mainstream car, like autonomous emergency braking (AEB), it does offer up more track-orientated safety components.

For starters, the seats feature a four-point harness, securing you snuggly into the fixed-back seats. This means you won’t move an inch, even when cornering at ridiculous speeds.

There is also a roll cage to keep the cabin secure in the event of a serious crash. And five airbags are fitted.

The SL63 4Matic+ will be covered by Mercedes-AMG’s five-year/unlimited km warranty, with roadside and accident assistance included for the duration, both of which are expected in this category. 

Maintenance intervals are 12 months/20,000km, and a fixed-price service plan lists an average of $1583 for each of the first three visits to the workshop. Not exactly small change, but not unheard of in this part of the market.

Like all new Mercedes models sold in 2021, the Mercedes-AMG GT Black Series comes with a five-year/unlimited kilometre warranty with roadside assist over that period.

Mercedes’ warranty easily outclasses other premium marques like BMW, Porsche and Audi, who each offer a three-year/unlimited kilometre coverage, and Lexus (four year/100,000km), while matching Jaguar and newcomer Genesis.

Scheduled servicing intervals are every 12 months or 20,000km, whichever occurs first.

Servicing costs for the Black Series were unavailable to us at the time of publishing, but maintenance of the GT coupe will ring the till up at $4750 over three years.