It was once thought that BMW was the German marque better suited to making corner carvers, and Mercedes-Benz was the brand which specialized in luxurious people carriers. Nowadays, it’s hard to make sense of where the two brands stand, since their offerings are so vast and generally capable, but nothing from BMW has the edge the sharpened version of Mercedes’ popular AMG GT has.

In fact, the hardcore AMG GT R has the ability to outrun a 991-generation Porsche 911 GT3, which, given its hard-edged reputation, should have no problem with a typical AMG. Unlike some of the porkier offerings from Mercedes’ in-house tuner, the AMG GT R is a real weapon on the track, and shares some of its makeup with the racing version.

Like the Porsche 911 GT3, it uses rear wheel steering to offer a level of precision that most couldn’t associate with those classic, long-hooded proportions. A massive diffuser at the rear offers incredible stability at speed (see 3:55 for a real demonstration of trust), and the low-speed traction is aided by the AMG GT’s electronic differential, as well as a nine-stage traction control system inherited from the AMG GT3 racing car!

With 585 horsepower and 476 lb-ft driving the rear wheels, people would assume that every corner would turn into a tire fry. Big torque is managed through calibration; the motor revs and produces power like a normally-aspirated AMG should, but there’s not much else holding it back if you discount that traction control system. Mind you, the system is only accessible when the ESP is disabled, so the guys at AMG were clearly interested in intruding as little as possible with the driving experience.

Making good use of the power, the GT R is able to gobble up straights and accelerate with respectable traction and minimal throttle cut—little corner-exit slides are managed with a hint of opposite lock. It’s still a complicated, heavy car, and that shows when it’s put up against the all-around performer which is the 911 GT3, against which it’s—almost imperceptibly—lazier. We’re talking shades of grey here, but there’s no getting away from the weight advantage the Porsche holds over the Benz.

The rear-engined GT3 ekes out gaps in the technical sections where traction is everything. The transaxle setup in the Benz can’t compete, the torque delivery is more brutal, and the car is slightly less manageable when the rears eventually let go.

However, the Porsche seems to suffer to match it in terms of front-end grip in the more technical sections of the Nordschleife. Since Sport Auto’s chief test driver Christian Gebhardt is not shy of testing the limits of the front axle by using strong steering inputs and deftly managing understeer through slower corners— ?t=1m59s”>his onboard lap with the GT3 at the ‘Ring supports that—he’s able to illustrate the distinction here.

It’s at the left-right flick at Adenauer Forst (2:16 in the Benz’s onboard footage) that the difference in front axle strengths is best seen. Into the corner, arriving at high speed from the preceding Fuchsröhre section, the Porsche is instantly limited by its understeer, and reluctant to turn in, which, having to keep some steering lock on for longer, is made worse by the right-hand flick at the exit of the complex. The front axle is overwhelmed, and the Porsche loses lots of time here, where the Mercedes does a quick flick-flick, keeps the mid-corner speed up, and relies on that incredible motor to fire it down the following straight.

As speeds increase, it’s the Porsche which looks more inviting; more controllable and more precise. While the Mercedes has an edge in slower corners, that incisiveness is lost in the faster stuff. It’s deflected over bumps, and not as predictable as the Porsche, which is aided by the rear-engined willingness to rotate in the quick stuff. It takes a sensitive pair of hands, but the GT3 allows the driver to thread the needle when the GT R becomes a comparatively blunt tool.

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Being a relatively fast course with lots of straighter sections, a torquey powerplant goes a long way, hence the AMG’s better time. Nevertheless, the car which looks to offer more in terms of driver involvement is the Porsche, and probably the better machine to try and whittle lap times down with. Yet, for a company better known for their luxurious sedans, the Benz is far from a pumped-up Riviera cruiser.