With an official debut expected later this year, Mercedes-AMG is getting ready to wrap up the development of the GT R.

However, that doesn’t necessarily mean that the range-topping version of the AMG GT family is willing to reveal all its secrets just yet, but until it does, prototypes like this one will continue to take center stage.

Caught out in the open, the powerful machine’s large rear spoiler is a giveaway, and so is its growling 4.0-liter V8 twin-turbo engine, which is noisier than the one equipping its two other siblings, the AMG GT and AMG GT S. The extra punch should bring the total output from 510 PS (503 HP) to around 550 PS (542 HP) or even more, as some reports indicate as much as 600 PS (592 HP).

In its upgraded form, the hardcore version will also feature plenty of lightweight materials, a modified suspension, larger brakes, new alloy wheels and a more aggressive body kit. These changes will place it in the same league as the Porsche 911 GT3 RS and even if it won’t be as large or as powerful as the SLS AMG Black Series, the AMG GT R promises to outrun it.

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