Of all the wild contraptions Mercedes has built over the years, the R63 AMG is among the most bizarre. Somehow, a V8-powered MPV received the stamp of approval from the higher-ups, thus paving the way for a people-mover that was able to hit 62 mph (100 km/h) in 4.6 seconds and top out at 171 mph (275 km/h). The R-Class was phased out five years ago, and while it was superseded by the V-Class, the biggest engine available is a V6 diesel.

This is where German tuner GAD-Motors comes into play as it has crammed a V8 inside the V-Class' engine bay. Not just any V8, but the twin-turbo 4.0-litre from the mighty AMG GT R supercar. "The Beast from the Green Hell" as it was nicknamed by the folks from Affalterbach pushes out 585 bhp and 700 Newton-metres (516 pound-feet). It, therefore, outpunches the old R63 AMG by over 70 bhp and 70 Nm (51 lb-ft) of torque.

Mercedes-Benz new V-Class

The high-performance family hauler was spotted being pushed hard at the Nürburgring by Andreas Gülden, the track's official Chief Instructor and Head of the Driving Academy. With great power comes great responsibility, so GAD-Motors matched the V8 engine with carbon-ceramic brakes also borrowed from the former fastest production car with rear-wheel drive at the Green Hell.

It's not every day we see an MPV at full throttle around the Nordschleife, let alone one that happens to have a big V8 under its bonnet. Being this large and heavy while having a tall roof, the amped-up V is obviously nowhere near as nimble as the track-focused AMG GT -R. We do like the virtually stock appearance of the MPV, making it a true sleeper provided you ignore the V8 BITURBO 4MATIC+ badge on the front wing/fender.

GAD-Motors mentions installing the M177 engine was not a plug & play solution as it had to develop quite a few custom parts, including a new exhaust system. It even has a catalytic converter and a gasoline particulate filter to meet emissions regulations, while the suspension was revamped as well to sharpen up handling.

With tightening laws and EVs taking over, it's safe to say Mercedes will never make a V8 MPV again, but the tuning scene has shown it has a soft spot for the V-Class.