Mercedes-AMG GT

	Mercedes-AMG GT
	Debut: 2014 Maker: Mercedes-Benz Predecessor: SLS AMG (C197)

Published on 29 Dec 2014

Interestingly, the flapship sports car of Mercedes-Benz goes progressively downstream over the last decade, from the £313,000 SLR McLaren to the £170,000 SLS AMG and now the £100,000 AMG GT (or £110,000 for the hotter GT S). This means it now clashes head-on with the mighty Porsche 911 in a much bigger market segment. Stuttgart has not revealed sales target, but obviously it is looking for more than 10,000 units annually, considering Porsche sold 30,000 units of 911 last year. In other words, one year of sales will easily match or exceed that managed by the SLS in its entire lifespan of 5 years.

The business case is more sensible not just because of keener pricing, but the new market positioning is more relevant to the existing line-up and customer base of Mercedes. The old SLS used to have an identity problem – it did not have a badge as exclusive or exotic as Ferrari yet it commanded the same price as the excellent 458 Italia. Just like Ferrari California, it was a mismatch of badge and talent. Now the reposition puts it at a market segment which demands solid build quality, luxury and everyday usability as well as performance and driving thrills. For long, Porsche 911 had been the only choice for this class. In recent years Audi R8, Aston Martin V8 Vantage and Jaguar F-Type R joined the competition but none of them quite rocked the status of Porsche. Can the AMG challenger do that?

Style-wise, the AMG GT is a bit more handsome than the SLS. Its body profile gets smoother, with a rounder nose, roof and tail, while a hatchback design is adopted instead of 3-box. It even looks a bit like 911 from the tail. The details have also evolved to be more elegant. However, it keeps the same long-hood, short-deck, cab-rearward profile of the old car as the mechanical layout is unchanged, i.e. a front-mid-mounted V8 and a rear-mounted 7-speed dual-clutch transaxle. Because of this, it also keeps the same excellent front-to-rear weight distribution of 47:53. On the downside, this Jaguar-E-type-like profile is not kind to airstream, thus its drag coefficient is rather poor at 0.36, a far cry from the high standards of Mercedes – no wonder it did not mention in press release. A tiny tail spoiler raises automatically at speed to cut lift.

At 4546mm, the car is 92 mm shorter than the SLS, though its width is the same at 1939 mm, and it is a bit taller at 1289 mm. The latter gives its cabin more headroom, especially when the seats are set a bit deeper. To ease access to the cabin, save weight and cut costs, the SLS' gullwing doors have been replaced with conventional hinged doors.

Just like the exterior, the cockpit of AMG GT looks classic yet elegant, perhaps even flamboyant. It is dominated by 6 large circular air vents, a wide transmission tunnel and chunks of flashy decors. The space offered is tight, because the upright windscreen is close and there is virtually no clearance left behind the seats. Unlike 911, the AMG GT is strictly a 2-seater, but it has a reasonable boot measuring 350 liters, which could swallow a couple of golf clubs through the hatchback. You sit low and, compared with 911, visibility is limited by the high waist line, long bonnet and thick rear pillars. In other words, some practicality is traded for sense of occasion. Otherwise, ergonomics is quite good, thanks to plenty of adjustment to the seats and steering wheel and the high-mounted touch screen. Build quality is exceptional for this class, at least matching Porsche. It is tastefully trimmed with leather, Alcantara, alloy and optional carbon-fiber. Many switch gears are bespoke to the car, while those coming from Mercedes parts pool are far from disgraceful.

The all-aluminum chassis is a further development from the SLS. Mercedes claims it is the lightest in class at 231 kg. The whole car is 80 kg lighter than SLS and 55 kg lighter than 911 Turbo (though the latter has 4-wheel drive and rear seats). All suspensions are classic double-wishbones type. Their wishbones, knuckles and hub carriers are made of forged aluminum. The front suspension is taken from SLS, whereas the rear is a new design, with the lower wishbone connected directly to the wheel carrier for better wheel control. Adaptive dampers are standard to the GT S and optional on the lesser car. The S is also benefitted with an active rear differential (instead of mechanical one), Porsche-style variable engine and transmission mounts, stronger brakes and beefier rubbers. These add 30 kg to its kerb weight.

And it gets more power, too. We all love the old 6.2-liter V8 for its great sound, revvability and outright power, but unfortunately it has been phased out of production under the pressure of reducing emission. Taking its place is the new AMG M178, a 4.0-liter twin-turbo V8. It shares the same bore/stroke dimensions (83.0 x 92.0 mm) and many key features with the 2-liter turbo on A45 AMG. These include spray-guided piezo direct injection, 10.5:1 compression, twin-VVT, a cylinder head made of zirconium (for better cooling), cylinder bores treated with nano-slide low-friction coating and forged pistons. Unlike the versions to be fitted to other AMG saloons and coupes, this one has dry-sump lubrication to let it position lower in the chassis and deals better with cornering g-force. To keep its size compact, its turbos are mounted inside the V, like the latest V8s of BMW and Audi. In standard form it boosts up to 1.2 bar, producing 462 hp at 6000 rpm and 442 lbft of torque from 1600-5000 rpm. On the hotter S model, boost pressure is lifted to 1.3 bar to produce 510 hp at 6250 rpm and 479 lbft of torque at 1750-4750 rpm. Responsible for transmitting the power is a Getrag 7-speed DCT, a development from the old car.

The GT S is good for 193 mph and 0-60 mph in 3.7 seconds, very close to the level of 911 Turbo. It’s not exactly there yet, because Mercedes is holding its potential for the upcoming GT3 and Black Series variants. Considering the AMG 2-liter turbo is good for 180 hp per liter, the 4-liter V8 is theoretically capable of 720 hp! Apparently, the GT S is only the starting point of development…

On the Road

Even as a starting point, the new twin-turbo V8 is already a good one. There is a little bit turbo lag at low rev to overcome, more than the VTG turbos of Porsche, but the power delivery is surprisingly linear for a turbocharged motor. AMG deliberately mapped its ECU to give this linear character, therefore makes it friendlier to exploit and feel like a normally aspirated V8 – the same tactic as Ferrari on California T. The V8 is flexible across the entire rev range. It revs sweetly towards the 7000 rpm cut-out, although you won’t get any more punch beyond 6250 rpm. The exhaust note tuning is another wonder. Mercedes-AMG is still the only one capable of giving a turbocharged V8 such a wild, bassy, NASCAR-like soundtrack. If you have never heard how the old 6.2 sang, you might mistake it with a good normally aspirated V8.

The AMG GT certainly feels very fast on the road, thanks to the immensely flexible engine as well as the much improved dual-clutch transaxle. It might share the same hardware with the old one, but its calibration makes a big difference, giving determined and responsive gearshifts.

The handling is much improved over the SLS. It feels lighter, more agile and more accurate to turn. No doubt AMG has learned from mistakes and spent more effort on the chassis tuning. Unlike its predecessor, its tail doesn’t breakaway easily, thanks to much enhanced traction and grip and tighter body control. When it starts sliding, it is more progressive, and you can adjust the attitude with throttle. Now you can finally push the AMG as hard as a Porsche or Ferrari in a race track, enjoying its fluid maneuvering and new found composure. The variable-ratio steering is progressive and precise, with decent if not first-rate feel. Automobile magazine praised it as “the best of any electrically assisted system today, Porsche included” because, well, it is actually a hydraulic rack – applause to AMG as it dares to resist the trend of EPS.

However, the 911 remains the better sports car. Although the AMG GT S is much improved over its predecessor, the Porsche is still more agile, sharper and more precise in control, especially the rear-drive normally aspirated models like GT3 or GTS. More surprising, the 911 rides better, too. That leads to the biggest flaw of the AMG: its suspension is simply too firm for modern sports cars, let alone one dubbed “GT”. On slow roads filled with bumps and portholes it rides uncomfortably even with adaptive dampers at the softest setting. Neither does it feel as composed as Porsche at high-speed cruising. This hurt its prospect as a cross-country GT. The lack of composure could also hurt its handling on less than perfect roads.

This and the cramped interior/mediocre visibility are the only reservations about the car. The GT counters with a unique style, high build quality and an excellent V8. It is certainly worth consideration if you look for something different to the mainstream 911. One thing is certain: it is a lot better than Mercedes’ last attempt yet considerably cheaper to buy.

Verdict:

Published on 21 Dec 2016

AMG GT R

The GT R – not to be confused with Nissan GT-R – is the fastest version of the AMG sports car until the ultimate Black series to arrive in a couple of years’ time. This means, it sits above the standard 462 hp GT, the 510 hp GT S and 557 hp GT C in the increasingly crowded hierarchy of the AMG GT family. The GT R is not only faster but it is also track-oriented, like Porsche 911 GT3 RS. You can easily see that from its shape, which gets a lot more aggressive and aero-biased. Its front grille has been enlarged to aid cooling and gets some vertical grille elements which are reminiscent of the 1952 300SL Panamericana race car. The lower intakes also get larger. The front air splitter is set lower and more pronounced. At both sides of the bumper are two narrow, vertical intakes which draw air to form "air curtain" around the front wheel arches to reduce drag and turbulence. At the rear, the most obvious change is the fixed carbon-fiber rear spoiler. The exhaust is now centrally mounted to make space for 2 large diffusers at either side of it. Between the taillights there is an additional air outlet opened to release hot air. AMG GT has always been a beautiful design. The R remains beautiful, but it replaces some grace with anger.

Although the big rear wing is only manually adjustable, some active aerodynamic aids are used elsewhere. At the bottom of the front overhang there is a movable carbon-fiber flap which can be lowered if the road is absolutely flat (it is activated at Race mode above 80 km/h). This creates venturi effect and guides the underbody air flow more effectively to the rear diffuser, resulting in 40 kg more downforce at top speed. Overall, the car makes 155 kg of downforce at top speed and a drag coefficient lower than the standard car – admittedly, the latter is not too difficult to achieve considering the standard car has a poor Cd of 0.36!

You might notice the car looks wider than before. Yes, the bespoke carbon-fiber front fenders and aluminum rear fenders increase its width by 46 and 57 mm respectively to house wider tracks and tires. The tires are now 10mm and 20mm wider front and rear respectively, and they are stickier Michelin Pilot Sport Cup 2 rubbers like 911 GT3 RS. They are shod around lighter forged alloy wheels.

The engine is still that 4.0-liter twin-turbo V8. Larger compressor wheels lift its maximum boost pressure from 1.2 to 1.35 bar. Accompanied with revised exhaust ports and compression ratio etc. results in 75 more horsepower, so the total output is 585 hp. It’s not quite as powerful as the latest E63 S (612 hp) as it lacks the latter’s twin-scroll turbos and enhanced intercooling in exchange for lighter weight and smaller packaging. The V8 breathes through a new lightweight titanium exhaust. Power is coupled to a lighter twin-mass flywheel and 7-speed twin-clutch transaxle. A taller first gear makes it more useful at launch, while shorter top gear and final drive results in quicker response and explains why its top speed is only 5 mph higher. The traction control is reprogrammed to offer 9-way adjustment.

The torque tube linking between engine and transaxle is now made of carbon-fiber instead of aluminum in the case of the standard car. The transmission tunnel is reinforced by carbon-fiber elements to increase the chassis' torsional rigidity by 7.5 percent. The diagonal braces in engine compartment have been converted to carbon-fiber as well.

The suspension of GT R keeps the forged aluminum control arms and knuckles etc. but it turns to manually adjustable coil-over spring/damper units to alter roll and dive characteristics. Continuously adaptive dampers remain. The rear suspension is added with Mercedes' first active rear-wheel steering in order to tame its handling and match Porsche. Also like Porsche, it gets adaptive engine and transmission mounts to limit movement of these heavy components at hard cornering. Braking is provided by "composite" discs (i.e. steel disc with aluminum hub) in size of 390 mm front and 360 mm rear, but for occasional visits to track, the optional ceramic brakes are absolutely worthwhile.

Finally, the GT R is only 15 kilograms lighter than the GT S, not particularly stripped-out for a track-oriented car. It keeps most creature comfort intact, so weight saving comes from mainly the titanium exhaust, lithium battery and carbon-fiber roof/front fenders/spoilers/torque tube etc. The fine static balance of 47:53 is unchanged, thanks to the transaxle layout.

On the road

How does it drive on track? Impressive. It is really fast, not only a lot faster than the GT S but also many rivals. Porsche said 991 GT3 RS good for a 7:17 lap in Nurburgring, but this AMG has just set a rear-wheel-drive production car record there at 7:10.9, faster than Gumpert Appollo (a thinly disguised race car, remember), Viper ACR and Lexus LFA Nurburgring. Only the all-wheel-drive 918 Spyder, Lambo Aventador SV and Nissan GT-R Nismo had been faster.

The V8 remains one of the most intoxicating elements of the machine as it is so responsive, willing to rev, and it makes really great sound, especially the mad pops and crackles at overruns. However, unlike the lesser models, the GT R now has a chassis to match. Its Cup tires offer a lot more grip. Traction is excellent for a front-engine rear-drive car, if not as impressive as mid-engined Ferraris or McLarens. Turn-in is much sharper. Roadholding is much stronger. Body roll is much tighter thanks to the stiff suspension setting. When it finally breaks away from the tarmac, its behavior is much more progressive, no doubt thanks to the 4-wheel steering. Compared with its siblings it has less understeer to overcome and a lot less drama to deal with when the car start sliding. On a track you can still manage the drift angle with throttle, but it is no longer the inherent nature of the car, because slide is the enemy to speed. You can push the GT R much harder on the track, brake later and reapply power earlier at corner exit. It has lifted performance to a whole new level – a level not far below the likes of 488GTB and 570S. It is a precise track machine, a rare achievement for an FR sports car.

However, with price starting at £142,000 (and can easily top £160,000 with ceramic brakes and other options), the GT R falls into a highly competitive class where many rivals are equally good. The AMG isn’t the quickest in straight line. Its steering doesn’t offer the best feel. Its dual-clutch gearshift is good but not as great as Porsche's. Neither is its traction as impressive. As much as we love the AMG M178 V8, it is not as sweet as the naturally aspirated boxer of 911 R. Most important, the GT R is more a hardcore track machine than anyone else. On less than perfectly smooth roads you will find its ride so stiff, even in Comfort mode, something McLaren 570S, Audi R8, 911 R, 911 Turbo S or Honda NSX managed to avoid. That’s the price of Nurburgring lap record, and what keeps it from matching its more rounded rivals.

Verdict:

Published on 19 May 2017

AMG GT C

It might just be the sweet spot of the increasingly vast AMG GT family...

What does C stand for? No one knows, not even Mercedes itself. Never mind, what we need to know is that it bridges the gap between the GT S and the track-oriented GT R. It might just be the sweet spot of the increasingly vast AMG GT family.

The GT C was initially unveiled as a Roadster, but hard top coupe joined shortly afterwards. Naturally, the Roadster is slightly heavier (by 35 kg) due to the soft top mechanism as well as some chassis reinforcement surrounding the cockpit. It sacrifices merely 1 kph on Autobahn, but in terms of handling and ride you will be hard pressed to tell the difference because the chassis feels just as stiff as the coupe. Both are powered by the familiar M178 4.0-liter hot-Vee V8, whose state of tune lies halfway between GT S and GT R. Its maximum output is 557 horsepower, while peak torque is 501 lbft. By the way, the base GT and GT S also enjoy a slight power boost recently (see spec. below).

“Panamericana” grille makes the car look angrier and more purposeful.

All AMG GTs now sport the so-called “Panamericana” grille like the GT R. It makes the car look angrier and more purposeful than the original. Unlike lesser models, the GT C also follows the exotic GT R to employ flared rear fenders which extend its body width by 57mm. They enable a wider track and 10mm wider rear tires. Like GT R again, the C is equipped with 4-wheel steering as standard, something improving its handling significantly. However, it does not enjoy the carbon-fiber diet of the range-topper. A GT C coupe tips the scale at 1625 kg, 55 more than the GT S. This is mainly down to the 4WS, the standard fitted adaptive dampers and active differential. For comparison, a 911 Turbo S weighs 25 kg less despite its 4-wheel-drive system. The Porsche is also slightly more powerful, no wonder it could claim 0-60 mph in 2.8 seconds, significantly faster than the GT C's 3.6 seconds.

Standing start acceleration has never been the strength of AMG GT due to its FR layout. However, in the real world the GT C never feels tamed. Its V8 howls angrily, especially with the variable exhaust opens its flaps. Benefited from the rear-wheel steering and wider rear track, its chassis balances much better. A GT S would understeer at the corner entry and then slide its tail if you commit too much at corner exit. The GT C corners smoother, with less initial understeer to deal with, and oversteer is much better contained. It is now a lot more predictable to push at tighter turns, even though it still can't match the traction and agility of 911 Turbo.

Its chassis balances much better...

The suspension rides firmly, but not as firm as the GT R. It is not going to be as comfortable as NSX, 570S or 911 Turbo on daily commute, but still easily acceptable for hardcore drivers. On the plus side, not many rivals could match the AMG’s visual appeal. Its exterior design is full of character. Its interior feels expensive and special. The Roadster’s 3-layer fabric roof is high-quality and the Airscarf seats keep your neck warm in winter. This means, although it costs the same as the 911 Turbo S and NSX, some people might find its packaging more than enough to compensate for its performance deficit.

Verdict:

Published on 19 Nov 2020

AMG GT Black series

The new Nurburgring lap record holder is a front-engined car.

Welcome back, Black series. Car enthusiasts won’t be strangers to the series. It is the hardcore performance label of AMG, or you may call it “the best of the best”. The first Black series car was introduced in 2006 in the form of SLK55 Black. It was then followed by CLK63 Black (2007), SL65 Black (2008), C63 Coupe Black (2011) and SLS Black (2013). We especially loved the last one, considered it as the purest AMG to date. Somehow, AMG has yet to repeat its magic on the current Mercedes-AMG lineup, until today.

Unlike its predecessors, the AMG GT Black series is designed to be a very expensive track-focused machine like the recent McLaren 765LT. It costs a whopping £335,000, more than twice the price of its next expensive sister, GT R. It makes the old SLS Black seemed good value at £230,000, especially when production of that car was limited to 350 units while this one is unlimited. In return, you get way more performance and significantly faster lap time than the GT R. Yesterday, AMG announced that it set a new production car lap record at Nurburgring in 6:43.62, just over a second quicker than Lamborghini Aventador SVJ. For a front-engine, rear-wheel-drive car, this achievement is quite incredible.

Lap time aside, is the GT Black worth the enormous amount of money it asks for? Let’s see what AMG has done to the car…

For starters, the Black series looks really like a thinly disguised racing car. Under its massive Panamericana front grille is a pronounced carbon-fiber front splitter, which is manually adjusted for a range of 80mm. There are more skirts and winglets, while the bonnet has a pair of air outlets and the front fenders have louvers to get air out of the engine bay – for improving both cooling and downforce. At the back, quad-exhaust moves to the sides to make way for a larger diffuser, while a huge, race-car-spec. double-plane rear wing tops the boot. Again the wing is made of carbon-fiber, and both of its foils can be manually adjusted to 3 positions. All aero changes combined, the Black can generate 400 kg of downforce at 155 mph, or 800 kg at its 202 mph top speed. If any road car can “out-RS” a Porsche GT3 RS on looks, this is it.

If any road car can "out-RS" a Porsche GT3 RS on looks, this is it.

Then comes the overhauled 4.0-liter twin-turbo V8 motor, codenamed M178 LS2. The most notable change is replacing the conventional cross-plane crankshaft with a low-inertia flat-plane crankshaft, like what Ferrari has been using for decades on its V8 engines. This necessitates revised firing order, new camshafts and exhaust manifolds to suit. Curiously, despite of the lightweight crank, its maximum rev is up by only 200 rpm to 7200. However, at the same time the M178 LS2 runs a much heavier turbo boost (1.7 bar instead of 1.35 bar on the GT R) thanks to a pair of larger turbochargers. As a result, the powerplant produces a Ferrari and McLaren-matching 730 horsepower at 6700 to 6900 rpm, which is far stronger than any other versions of the M178 V8. Meanwhile, peak torque rises to 590 pound-foot, not quite matching the 664 lbft number of AMG GT 4-door, but this is likely to be limited by its DCT transaxle. Anyway, 590 lbft already matches that of McLaren 765LT, and it is available across a much wider band, between 2000 and 6000 rpm.

Meanwhile, AMG engineers also cut weight from the car. The bespoke bonnet, front fenders and roof are now made of carbon-fiber, as is the torque tube backbone and the prop shaft. Weight reduction can be found also inside the cabin, such as carbon-fiber bucket seats and lightweight door panels. The front and rear screens are made of thinner glass, too, although part of the reduction is offset by the fitment of a titanium semi-roll cage. Overall, the car weighs 1520 kg, 35 less than the GT R. Admittedly, it is still way heavier than the McLaren 765LT (1339 kg), Ferrari 488 Pista (1385 kg) or Porsche 911 GT2 RS (1440 kg), blame partly to its FR layout and partly to its mainstream aluminum construction. The FR weight distribution also means less rear-wheel traction available for standing-start acceleration, so the official 0-60 mph time is relatively unremarkable at 3.1 seconds. Ditto the 0-124 mph claim of 8.9 seconds, which is 1.7 second adrift of its McLaren rival.

The Black is 35 kg lighter than the GT R, but still considerably heavier than its McLaren, Ferrari and Porsche rivals.

The chassis of Black is reinforced by some underbody shear panels and cross braces around the transmission tunnel. Its suspensions are developed further from the GT R. Like the latter, it employs coil-over spring/damper units. Front and rear camber as well as anti-roll bars can be adjusted manually. Soft compound Michelin PS Cup 2R tires are offered, and they are 10 mm wider than those fitted to the GT R.

On the Road/Track

Needless to say, the Black carries over the ergonomics limitation of other AMG GTs. Its cockpit is snug, dominating by a prominent transmission tunnel thus you have little elbow room to stretch your arms. Neither are headroom and legroom too generous. The windscreen is shallow and very close to your head. Unlike its mid or rear-engined rivals, the view forward is far from expansive. A long long bonnet limits visibility, while rearward view is not great either. In short, a claustrophobic environment.

Start the motor, you will immediately notice its different character. The sound is unlike any AMG V8s. Loud? unquestionable. Mellow? No, it is gravel, edgy and angry, like a pair of four-cylinder bike engines bark at the same time, thanks to that flat-plane crankshaft. Power delivery is strong. Maybe there is a touch more turbo lag than Ferrari V8, or the throttle response is not quite as sharp, nor its DCT transaxle can match the response of Maranello’s, but the AMG engine is far stronger at the mid-range than a McLaren V8, which needs 5000 rpm or more to feel really quick. You had better to keep the AMG at over 4000 rpm, but even lower down it still pulls forcefully and linearly enough to be considered as a supercar, while at the top end it feels just as intoxicating as its Italian and British rivals.

On track, it shines in all the areas racing drivers care...

The regular AMG GT always rides stiffly, so predictably the flagship model is even more hardcore. You wouldn’t want to drive it on a mountain road as you would in a 488 Pista, GT2 RS or GT3 RS (McLaren 765LT has yet to be driven on roads, but it seems to be more forgiving than the Black as well). Don’t think it is a road & track dual-purpose car like those. The Black is a hardcore machine designed primarily for track abuse.

So it feels at home on track, especially wider and faster ones. It shines in all the areas racing drivers care: braking? phenomenal. Grip? huge. Stability? reassuring, especially at higher speeds where downforce is felt. Steering? Talkative, much better than GT R’s, if a bit too light for some tastes. Compared with Porsche GTs or any McLaren LTs, the AMG does display more body roll and pitch under braking. In slow corners, it tends to understeer, which makes it more predictable and less edgy than some rivals, but at the same time less playful. If you switch off ESC and turn its 10-setting traction control to the least intervening positions, you can use throttle to balance the car, but still it is not a born drift machine. The Black prefers its driver to guide it in a smooth, measured way. The “slow-in, fast out” technique for driving classical FR GTs is applicable here. Racing drivers might love that, especially when it helps breaking the Nurburgring lap record. However, if you pursue for the most thrilling driving experience, exercising throttle, steering and braking to balance the car at the limit and in the process enjoying its razor-sharp response and keen feedback, then this car is not for you.

Being a front-engined GT, it is almost unique in the field of track-oriented machines. The fact that it matches the best Porsche GTs and McLaren LTs in most areas is quite incredible. However, that is not enough to justify its high price. Some of its rivals are more thrilling to drive. Most are faster on paper, and nearly all come with a more exotic mechanical layout and a more prestigious badge. In the end, the AMG GT Black series has only one advantage: Nurburgring lap record. But for how long?

Verdict: