Mercedes-AMG GT4 review: is it as scary as it looks?

By topgear, 08 May 2019
Mercedes-AMG GT4

Yikes. That looks angry.
Doesn’t it just? This is the Mercedes-AMG GT4, a racing car based upon the already very unhinged AMG GT R. You’d be forgiven for scurrying behind the nearest sofa at the mere sight of it.

AMG’s motorsport people have taken the GT R, a 577bhp sports car with a seething disdain for tyre longevity, and stripped out all the stuff you don’t need on the race track – a stereo, climate control, any semblance of connectivity beyond a pit radio – and added in the stuff you do. A roll cage, FIA-approved seating and a sequential gearbox, to name just a few highlights.

I presume it’s dieted?
With exhaustive use of carbon, especially inside, the weight has fallen almost 300kg, the GT4’s 1,390kg comparable to a hot hatch. Its power, naturally, isn’t; it gets the same 4.0-litre twin-turbo V8 as the AMG GT S, here producing 503bhp and 601Nm.

Not the same engine as the GT R, you’ll note, and for numerous reasons. Less boost means less turbo lag, and because of the occasionally stringent ‘Balance of Performance’ rules of the competitions the GT4 is eligible to enter, there are times it might be strangled to below 450bhp, so there’s little point in having vastly excessive power beforehand. But the GT4’s strict diet means its performance is comparable to the more powerful GT R road car, with 0-100kph dealt with in less than four seconds.


What else has changed?
The driver sits inside a carbon safety cell and there’s a similar electronic set-up to the much burlier AMG GT3 racecar. That means an iteration of its bigger brother’s traction control system and sequential gearbox, the latter being a big deal. The GT4 category is burgeoning, with everything from Alpines and McLarens to Camaros and M4s represented, so having such senior components helps set AMG’s competitor apart.

“It’s got to be one of the most advanced GT4s out there,” says Merc GT3 driver Adam Christodoulou, who also played a hand in the GT4’s development. “It’s a GT3.5, almost. GT4s are now incredible machines and this is one of the only examples with the full race gearbox and wiring loom like our GT3 car’s got.

“Its seat fits straight into the GT3 car, too. All of your pedal settings can go straight across so the quicker car will feel close to home as they’re so similar on the inside. A lot of single-seater drivers make the switch to GT4 because it’s a more affordable way into GT3 cars.”

So it’s a stepping stone into more senior motorsport?
Correct. This is a car aimed essentially at those in the early years of their career, or amateur drivers with a bit less confidence. That’s certainly a position I can empathise with as Adam shows me around the car, before inviting me to clamber in. Initially that’s not a huge ask, as unlike the AMG GT3, the door’s still full size. But once submerged in the cabin, peering over the slimmed-down, barely there steering wheel, the intimidation creeps in.

As he sends a mechanic off to find some booster cushions to hike me up, I’m shown all of the various buttons including the traction control dial. It’s pleasingly similar to the roadgoing GT R’s, but given the light sprinkling of rain outside, I’ve no intention of messing with the settings Adam’s left me – level six, slap-bang in the middle.

Suitably boosted in height, I then make sure I can prod each pedal to its stop. They feel spaced for left-foot braking, but when I’m told both left- and right-footed approaches will work, I decide to stick to what I know best and only use my left leg to engage the clutch, something required when using first gear in the pitlane, but no other time. The rest of the time you shift clutchlessly, with your right foot flat to the floor.


Sounds proper…
Indeed, and after the kerfuffle of getting fitted into the seat and the alien experience of grabbing a wheel no wider than my own hands, the GT4 could give the impression of a predator poised and ready to maul me the second my courage wavers.

It turns out to be a pussycat. Perhaps it’s the softened engine tune, or the surfeit of grip, or the cleverer aero. It’s likely a mix of all three. But no AMG GT road car has ever had me driving as hard as this so quickly, the damp track beneath a mere incidental detail.

You’re always flat, upchanges slamming home with plenty of physicality but no upset to the chassis beneath. Finding enough cushioning for my weedy height meant I had too little time to locate the rev-counter on the titchy, info-laden screen behind the wheel, so I’m fully reliant on the shift lights above. It’s a real thrill to hang on for a fully illuminated line before pulling the right-hand paddle with conviction.

So the sequential’s friendly, and it’s complemented on downchanges by a brake pedal that’s a doddle to unsympathetically mash. And you can brake so fantastically late. Losing speed is far more dramatic than gaining it, the acceleration strangely muted because everything is so smooth and easy. No scrabble for traction like the road car, no squirm of the wheel as the rear tyres attempt to convey buckets of torque… it’s less challenging than even a GT S in a straight line, but it’s much more of a talent barometer in the corners.


How so?
How late dare you brake before the corner? How much speed dare you carry around it? On my first go in a GT4 car – with a bunch of bona fide Mercedes racing drivers nearby, not least my tutor Adam and some bloke called Lewis – my responses appear to be ‘not very’ and ‘not much’. Certainly not by the car’s evidently high standards.

But I drive harder than I’d dared imagine as rain pattered on my helmet in the pitlane, the car spurring me on to dig deeper and deeper into its vast reserves of grip. I’m revving out five of its six gears within my first lap, getting on the throttle so much earlier in corners than I’d expected and wringing out more performance and I’d ever have dreamt.

Every time I up my own commitment, the car responds without fuss. A handful of laps of Silverstone are not enough for me to find anything like this car’s limit, and I can only make an educated guess that, at the moment, it sits very far above my own.

Not so angry after all, then.
“This thing’s got to be evenly balanced and predictable and consistent,” Adam tells me. “If it doesn’t give you confidence, the less experienced drivers are going to struggle.”

Indeed, the AMG GT4 certainly feels amiable, well-built and willing to take some ham-fistedness from drivers who fall short of supernatural ability. If I had the spare 198,850 euros (about RM924,000) I’d find this a much more enthralling place to put it than a peacocking supercar.

Those are so well endowed these days that an expensively honed racecar on proper tyres can’t help but feel sanitised in comparison. Even Ferrari’s softest car, the comparatively priced Portofino, has nearly 100bhp more than this. But the depth of ability (and geekery) in this GT4 carries so much more credibility, while there’s a wealth of support from Mercedes when you do take the plunge. If AMG’s brief is to be a welcoming lower rung on a very exciting ladder, it’s absolutely nailed it. How I want another go, to really do this thing justice.