Fast, furious and comfortable, the new GT ‘sedan’ might just be the flagship AMG deserves
What we liked:
• Grown-up ride quality
• Enormous interior space
• (Almost) idiot-proof handling
Not so much:
• Mega hefty
• Droopy-bum looks
• Not an actual GT
The Mercedes-AMG GT 4-Door Coupe proves to be a surprisingly good all-rounder, with tremendous speed, clever cornering technology, terrific engines and ride comfort to spare. It’s not flawless but it’s close enough to sit deservedly atop the AMG GT tree and provide the Porsche Panamera Turbo with tough competition.
Not so fast
It would have been easy to be cynical about the Mercedes-AMG GT 4-Door Coupe.
After all, it attempts to leverage the two-door AMG GT’s name and design, but its only technical connections to Mercedes-Benz’s Porsche 911-fighter are its engine, gearbox and its front and rear looks.
And yet it mostly works. And that’s something of a surprise and a testament to the value of clever scaffolding.
Beneath its contrived, stretched banana of a four-door ‘coupe’ body, the GT 4-Door isn’t a stretched GT. That would have entailed an enormous amount of creative aluminium spaceframe shenanigans and it seemed altogether easier just to stretch out the well-received E 63 instead.
So that’s what AMG, but it found some issues in poking in an extra 65mm of overall length and another 12mm into the wheelbase.
The amount of extra bracing beneath the body-in-white needs to be seen to be believed, with a carbon-fibre rear bulkhead tasked with most of the stiffening duties around the back (though supported by struts in the luggage area and more beneath the floor), while a solid aluminium plate sits under the engine compartment to stiffen the front.
There’s more, with long diagonal braces running from the middle to the rear and three more cross braces on the transmission tunnel. The naked bodyshell looks like it’s been accosted by a building site.
The interesting bit here is that AMG has tried to cram so many GT design “signatures” into a big five-door – you could even call it AMG’s Porsche Panamera, the competitor which has similarly suffered from the design insistence of product planners.
There’s the grille, obviously, and the tail, which is equally obvious, yet in between is, err, nothing at all related to the GT.
The best visual version of this layout in modern times has been the Audi A7 and RS 7 but the new one seems to have lost its magic, so the GT arrives at a low-water mark for premium five-door design, which might allow AMG to get away with it.
It’s a big machine inside, too, with seating for five and a step up in rear legroom that seems at odds with the narrow margin of its wheelbase advantage over the E 63.
It will be priced accordingly, too, with an incremental step up from every similar powertrain in the AMG versions of the E-Class when it arrives here late in the first half of next year.
There won’t be a (non S) GT 63 4-Door, though, because Mercedes-Benz Australia thinks people would just rather add another 100Nm and take the GT 63 S instead.
Pick of the bunch
There will be the new 53 powertrain, which combines the smooth musings of the new straight-six 3.0-litre turbo motor with the silent urgings of a 250Nm electric motor.
Now, this isn’t going to be the sexy thing to say, but it’s actually the pick of the new Mercedes-AMG GT 4-Door Coupe family because it’s not dominated by the thump and bellow of its engine, which lets you absorb a bit more of the machine around you.
It’s something of a surprise because while you expect modern AMGs to be powerful and fast, you rarely expect them to broaden their scope enough to include subtlety and apparent sophistication. But that’s what it does.
It’s technically every bit as fun as the thumping 4.0-litre biturbo V8 in the GT 63 S Coupe, but it’s far more capable of acting like the adult in the room when it has to as well.
Sure, the V8 can do that if you organise the right modes and exhaust switches, but it feels like that’s masking its true identity, where the 53 powertrain feels like it’s inherent in its character.
The 3.0-litre straight six is a very good engine to base things off, with a turbocharger, variable valve timing and lift and even cylinder deactivation for cruising delivering 320kW of power and 520Nm of torque.
The fun bit comes when AMG adds an extra 16kW of power and 250Nm of torque from the powered-up integrated starter-generator attached to the flywheel.
It ties in with a 48-volt electrical system and a separate lithium-ion battery to feed more in at the bottom of the engine’s torque curve and for those instants when the turbo isn’t yet on song.
It virtually eliminates turbo lag, fattening things up via electric boosting of the crankshaft, and helps the GT 53 to 100km/h in 4.9 seconds on its way to a 270km/h top end.
The added bonus is that it pulls the official fuel consumption figure down to 9.1L/100km.
But my favourite parts of it are when it is under part load or around town, when you step on the accelerator and find a strong, drama-free surge forward combined with the sweet, muscular howl of the straight six.
The two power sources are nearly totally absorbed with each other and virtually coherent, making it impossible to spot where one begins and the other ends.
It also gives you more time to appreciate the best parts of the GT sedan’s chassis architecture, with four links to the front suspension and five at the back.
With the lighter six-pot lurking over the front axle, the handling is sweeter and crisper, taking advantage of the GT’s rear-wheel steering by carrying only 1965kg (gulp) compared to the V8’s 2045kg of mass – and that’s without the driver.
The ride quality is surprisingly calm and clever, given it’s riding on 255/40 R19 front and 285/40 R19 rear Pirelli rubber.
Like its faster brethren, the 53 runs active aerodynamics at both ends, including a version of the GT R’s active front splitter, and it also apes the V8’s active all-wheel drive system.
That works seamlessly in the six-cylinder version and there’s something about the lightness on its toes and the overall balance of the car in steering, handling, ease of use in town and its generally friendly nature that seems to mark it down as the GT Coupe to live with, rather than make headlines with.
The 3.2-second bomber
Of course, making headlines is no bad thing when that’s what the situation calls for, so dialling up 470kW of power and 900Nm of torque from just four litres is a helpful little addition.
Few other car-makers would have the audacity to launch such a heavy car at a racetrack, much less at the Circuit of the Americas (COTA), which is one of the toughest tests of chassis around.
COTA has blind crests, long bends, tightening-radius esses and, as a bonus, a reputation for eating tyres. (Well, BMW did launch the M version of the last M6 here, but it didn’t quite impress like the GT 4-Door.)
It’s an odd thing to punch around at a track like this, hauling well beyond 270km/h on the back straight and turning in to corners in a way that belies its wheelbase.
The rear wheel steering and the ever-sharper driver-assistance systems (including a Race mode, would you believe, on a two-tonne car) make it fairly easy to throw around between the turn-in point and the apex.
It’s a lot more fun than you’d ever give it credit for if you ever weighed one or had one run over your foot. It’s also a lot easier to drive quickly than one American journalist showed when he destroyed his GT 63 S 4-Door Coupe by bouncing off two walls at COTA.
There is always something non-linear about the inputs the car gives you as it takes very well educated guesses about what you’re after and computes them brilliantly to put it all somewhere pretty close to the apex.
You can drift it into an apex with the tail sliding gently and easily, you can understeer if you want to (and, trust me, the car wants to so you have to convince it otherwise) or you can talk it into being neutral.
It stops brilliantly and consistently, too, on its 390mm composite discs and six-piston callipers up front and 360mm discs and single-piston floating callipers at the rear.
The one thing you can’t talk it out of is understeering under power after the apex, as you try to gather speed on the exit of the corner.
For all the chassis-poise fiddling and adjusting it lets – nay, encourages – you to do at the first half of a corner, it seems to run out of ideas after that, as though it’s exhausted its repertoire of digital and mechanical tricks and just wants you to hit the straight parts and punch on again.
And it does that part very, very well, as ever. The full thump of 900Nm arrives at 2500rpm and the power is still delivering at 6500 revs. It tails away beyond that, but it’s all backed up by the thunderous bellow of thick cardboard being ripped by hand.
It’s enough to reach 100km/h in 3.2 seconds, which is fast in anybody’s book, but incredible for a petrol-fuelled five-seater, and runs on to a 315km/h top speed.
The nine-speed automatic transmission, backed by a wet-clutch pack of AMG’s own design, is a clever piece of kit, too, as is the all-wheel drive system that changes the amount of drive each end receives on demand.
The trick, though, isn’t that the Mercedes-AMG GT 63 S 4-Door Coupe does a passable job of driving faster around a racetrack than most of its owners will ever need it to.
It’s that it does all of this and retains its good manners on the road, whether there are bumps or not, and whether there are highways or the rough city backstreets that can only be found looking for local coffee hangouts.
Even the six-cylinder version scores multibeam LED headlights as standard kit, along with steel springs and an adaptive damping system. It changes inside with a choice of either two crafted rear seats or a flatter three-seat bench.
The V8 upgrades to a multi-chamber air suspension set-up, along with an electromechanical limited-slip differential at the back-end, plus it scores active engine mounts to stiffen the mounts in sportier modes or soften them off for added comfort in the more cruisy ones.
Its dash display runs the full 31.2cm wide-screen digital display (optional on the 53), doubling as the instrument cluster and the infotainment screen, with a speedo that runs up to 360km/h.
The V8 is loaded inside, too, with a Burmester surround sound system, 64 ambient colours for the interior (this is a big deal in China, apparently).
Every seat in the car is tremendously comfortable and the driving position is intuitive and easy to find. It’s full of every piece of connectivity from Benz’s impressive array of such things, yet it still has 461 litres of luggage space.
The 63 S uses six drive programs, including Slippery, Comfort, Sport, Sport+, Individual (which can be customised) and Race.
On top of that, there are steering-wheel dials and/or centre-console switches so you can change each part of the car independently, like the exhaust noise or the damper stiffness or the gearshift aggression.
It’s a car that could easily have spun out of control – like a certain American did during our test – but it’s to AMG’s credit that it didn’t.
Mercedes-AMG might not have created a four-door GT, exactly, but it has created a very good grand touring car. Now, if AMG could just slash a few hundred kilos out of it…
How much does the 2019 Mercedes-AMG GT 53 4-Door Coupe cost?
Engine: 3.0-litre inline turbo-petrol mild-hybrid six-cylinder
Transmission: Nine-speed dual-clutch automatic, all-wheel drive
Safety rating: TBC
How much does the 2019 Mercedes-AMG GT 63 S 4-Door Coupe cost?
Available: Q2 2019
Engine: 4.0-litre twin-turbocharged petrol V8
Transmission: Nine-speed dual-clutch automatic, all-wheel drive
Safety rating: TBC