Mercedes-AMG GT R PRO 2021 Review

While it presupposes knowledge of Porsche’s 911 hierarchy, the easiest way to describe the 2021 Mercedes-AMG GT R PRO’s place in the world is to call it the Affalterbach alternative to the Porsche 911 GT3 RS.

Pretty simple really. This is the racetrack-fettled version of the sportiest mass-produced variant of the Mercedes-AMG GT family.

It’s not cheap at over $450,000, but the irony is it owes its place in the local Mercedes-AMG line-up to the most expensive AMG GT ever – the circa-$800,000 AMG GT Black Series. Indeed, it was the sell-out success of the Black Series that prompted Mercedes-Benz Australia to bite the bullet and commit to adding the Mercedes-AMG GT R PRO to its local line-up.

Even so, just 15 of the GT R PROs will come Down Under. Benz sources say they are the last 15 to be produced.

Thus with 28 examples of the AMG GT Black Series on their way to Australian owners, the GT R PRO ranks among the rarest of AMGs to hit the road locally.

The official price-tag for the 2021 Mercedes-AMG GT R PRO is a hefty $453,200 plus on-road costs. That price includes the Track Pack that’s optional in some markets, but it’s still a considerable $84,500 price premium over the ‘regular’ Mercedes-AMG GT R ($368,700 plus ORCs).

Mercedes-AMG titles the GT R PRO as “the ultimate track day racer of the Mercedes-AMG range” but stresses it is still able to be driven daily on the road.

To this end it retains conventional three-point seat belts in addition to the Track Pack’s four-point harnesses and the normal complement of safety and connectivity equipment.

Engine outputs are unchanged from the GT R and the running gear is much the same but there are detailed changes to aerodynamics, suspension, body work and interior – most aimed at improving the PRO’s abilities on the racetrack.

The majority of the mechanicals on the 2021 Mercedes-AMG GT R PRO are all but identical to the Mercedes-AMG GT R. At least in terms of the hardware – the same stonking 430kW/700Nm 4.0-litre twin-turbo dry-sumped M178 petrol V8 matched to a transaxle-style seven-speed dual-clutch gearbox and active differential.

For more details you can read our GT R update first drive and drives of other variants of the Mercedes-AMG GT including the AMG GT C and the original AMG GT S.

The devil is in the detail of the GT R PRO, however, and that detail involves a lot of racetrack development, much of it applying learnings from the AMG Customer Racing division’s multiple seasons campaigning the AMG GT3 and newer AMG GT4 racers.

Most changes to the PRO are subtle rather than wholesale.

It gets the GT R’s adjustable traction control and additional stability control system smarts including a race mode that acts as a hand of God for amateurs who confuse their ambitions with their capabilities.

But hard parts that are changed include the brakes (carbon-ceramic on all four corners) and the addition of a carbon-fibre undercar brace that bolts up the transaxle and prop shaft tunnel to increase chassis rigidity. Active engine mounts (which work like active dampers) stiffen to further mate drivetrain and body for more precision on the track.

The biggest hardware changes are in the suspension system and settings. A new carbon-fibre front anti-roll bar is fitted and a hollow alloy tube unit replaces the GT R’s items. Both are adjustable with tools (as opposed to in-cabin like the GT3 car).

Dampers front and rear are also adjustable for both high- and low-speed damping circuits on both compression and rebound. Spring preload can also be adjusted and via that ride heights.

The inveterate fiddlers out there should therefore be able to tune the Mercedes-AMG GT R PRO to a standstill. Or they can tap into head office’s smarts for detailed set-up instructions.

Other changes include gearbox calibration and the PRO shifts with even more speed and precision than the GT R. On the track, the shifts are for all intents and purposes whip-sharp… There’s no place for a manual gearbox in cars like these where computers and mechanicals combine with ruthless efficiency.

How does the running gear and suspension settings cope with the real world? Apologies, we can’t tell you – our time in the car was limited to laps of a track.

Two carbon-shelled, fixed-back, race-style, AMG-logoed seats look the part and the GT R’s gloss carbon-fibre interior trims including the centre console are swapped for matte clear-coated pieces in the PRO.

In fact, ‘lightweighting’ is a theme for the Mercedes-AMG GT R PRO.

As noted above, ceramic brakes are fitted on all four corners (the R gets carbons up front only) and lighter 20-inch AMG Performance five-double-spoke forged wheels are standard.

Carbon-fibre is used for the roof, specially braced front splitter, front quarter vents, side sill trim strips and rear diffuser. The GT R PRO also features CF side mirrors and adjustable rear wing which sports a gurney flap for added downforce.

An example of the detail AMG has gone to for its track-focused customers is a reprofiled roof liner – to give taller customers more room when wearing a helmet.

Even the badging gets a tweak. In lieu of a plain background on the GT R badge on the tail, the GT R PRO sports a chequered flag motif.

For the record, AMG says the PRO is more than six seconds quicker over a lap of the Nordschleife than the ‘standard’ Mercedes-AMG GT R. With a best time of 7:04.632, the PRO is, however, a substantial 21sec slower than the now record-holding AMG GT Black Series.

Comparing apples with apples, the best comparable time yours truly could find for a Porsche 911 GT3 RS around the benchmark German track was around 6:56.400.

AMG still has some work to do it seems. Well, they brought up The Ring first…

With the Nordschleife a touch hard to get to during the pandemic, there’s arguably no better local layout to experience the competence of the 2021 Mercedes-AMG GT R PRO than the Phillip Island GP Circuit.

This is a track made for cars like the AMG and the GT R PRO is a car made for tracks like Phillip Island.

First impressions are lasting impressions when it comes to big, powerful rear-drive sports cars. They can either instil confidence or they can gnaw at it. The PRO is very much a case of the former.

Balancing the needs of a track car and a road car, the 2021 Mercedes-AMG GT R PRO pulls away fuss-free with none of the jerky histrionics some lesser track-focused specials require you to manage.

But once the pit speed limit sign is passed and you unleash the twin-turbo V8's significant bottom-end torque, there’s no mistaking this car’s intentions.

On anything but warmed tyres, the traction light is blinking but there is little of the squat and shimmy that the normal AMG GT delivers. It’s more a momentary pause and then the full force of the car’s turbo torque number.

The steering is heavier than some will like. But it’s also extremely direct, extremely linear, and the front-end delivers confidence from almost the first corner. And then as you build speed, the absolute lack of unwanted free play in the suspension and overall response encourages you to push harder.

Rigid spherical bushes in the rear suspension mean that feedback to the seat of the pants is almost instant like a decent race car. Great on the track but likely to be a pain on the road.

And following a standard AMG GT R, it's pretty clear that the GT R PRO needs less real estate to circulate at the same pace. It's not long before you’re eating up enough of the gap under brakes into Phillip Island’s slower corners for the road-car-sourced AEB to start chiming in.

Power down out of corners also seems to be better on the track-focused car despite the two rolling on essentially the same tyres. With a proper racing driver perhaps the gap would not be as pronounced but it's fair to say the GT R PRO flatters even moderately skilful amateurs.

The last AMG GT I drove was the full race-car-spec GT4 variant. In comparison, despite being on street-legal treaded tyres, the Mercedes-AMG GT R PRO not only feels it has as much lateral grip but it also feels more predictable and confident on turn-in even at a decent pace.

There’s significantly more power on tap in the PRO than the GT4 (430kW v 375kW), and despite the road car’s extra weight, I've got little doubt it would have the race car’s measure over a lap at a track like Phillip Island.

The road-based gearbox is also more responsive and demonstrative in the PRO. Shifts are faster and sharper especially when the car is run in race mode.

Professional racers who have driven the Mercedes-AMG GT4, AMG’s race-winning GT3 and the GT R PRO say that the new road car has more in common with the big-gun GT3 in terms of chassis balance and grip than the gentleman-racer GT4.

Mind you, your AMG GT R PRO road car is going to set you back around $90K more than the GT4 racer. That in itself would make it a hard decision for someone like me.

Fortunately, the PRO is sold out. Plus there is around 450,000 reasons why I’ll never have to make the choice.

How much does the 2021 Mercedes-AMG GT R PRO cost?
Price: $453,200 (plus on-road costs)
Engine: 4.0-litre twin-turbo V8 petrol
Output: 430kW/700Nm
Transmission: Seven-speed dual-clutch automatic
Fuel: 11.4L/100km (ADR Combined)
CO2: 259g/km (ADR Combined)
Safety rating: Not tested