On a passenger ride in the range-topping 577bhp sports car, we recorded a lap time of 7min 46sec while being driven by Thomas Jaeger, one of the GT R’s principal development drivers. AMG insiders are now suggesting that a full-speed run will be between 20 and 25sec quicker than that. If achieved, that would put the GT R close to the 7min 20sec time of the 13.9-mile circuit that the Porsche 911 GT3 RS claimed last year, and maybe even the 7min 18sec set by the revised 911 Turbo S.
There’s no doubt that the GT R will become the fastest car in Mercedes’ line-up when it goes on sale later this year. Frank Emhardt, the car's development boss, reckons that we should see a Nordschleife lap time as being a better metric of overall performance than the car’s straight line performance numbers (an impressive claimed 0-62mph time of 3.6sec). “It is probably the toughest overall test for any performance car,” he said of the Nürburgring.