This snappily titled thing is the Performmaster Mercedes-AMG GT 63 S 4-door Coupe 1 of 31 Limited Customer Edition. Got your breath back yet? Well, the 731bhp this thing puts out will probably take it away all over again. 

Now, with 631bhp on tap, the standard GT 63 S 4-door is not exactly short on power. However, all it takes to squeeze out the extra ton is a bit of electronic trickery in the form of a PEC tuning module from the AMG specialists at Performmaster.

When connected to the 4.0-litre twin-turbo V8, the module also ups torque from the standard 664lb ft to a rather obscene 760lb ft (or over 1,000Nm if you’re on the continent). 

The updates mean that 0-62mph is dispatched in just 2.9 seconds – outrageous in an internal combustion-powered saloon car – although top speed stays the same at a not paltry 196mph. Presumably so the monster Merc doesn’t shred its tyres thanks to a two-tonne plus kerb weight.