Power and torque peak at 791bhp and 1055lb ft, or 179 and 391 more than the old 5.5-litre V8-engined S63, making this the most powerful S-Class yet. Unsurprisingly, though, it all comes with an additional 309kg to the kerb weight, at 2520kg.
With AMG’s nine-speed automatic gearbox and fully variable four-wheel drive system deploying these enormous reserves, it can hit 62mph in a mere 3.3sec.
All impressive figures, but can this larger and heavier S63 deliver similarly engaging performance and dynamics as its highly rated predecessor?
There are seven driving modes, named Electric, Comfort, Battery Hold, Sport, Sport+, Slippery, and Individual, which gives the big saloon extraordinary breadth. In everyday driving, it’s Comfort that makes the most of the complex powertrain, relying on a combination of both petrol and electricity but always proving highly refined and urgent on the motorway, and giving the impression that there’s always a lot more in reserve.
Extend the revs into the business end of the dial on a lonely road in Sport+ and there’s true sledgehammer performance in the best of AMG tradition, as the torque of the motor compensates for any fleeting pause as the turbos spool up to full force.
Once they do, the S63 accelerates like a supercar as its 4Matic+ system and electronically controlled limited-slip differential work their magic, contributing to outstanding traction and terrific determination on a loaded throttle. However, the combination of two separate gearboxes and the 4Matic+ system doesn’t always manage to handle the heady reserves with the aplomb we’ve come to expect from an AMG. We felt some unruly shunt, both at low speeds and at a faster lick out of town.