The new pictures follow a leak on a German car forum from earlier this year, which revealed the performance figures of the upcoming super saloon months ahead of its global reveal.
When translated, the two-page document suggested the E 63 will produce 603bhp and 627lb ft of torque from its twin-turbo 4.0-litre V8 engine in S spec, while the regular E 63 will produce 563bhp and 553lb ft of torque. This backs up earlier claims that the engine (which is a wet-sumped version of the dry sump unit featured in the 510bhp AMG GT) would be capable of more than 600bhp, and ensures the 2016 model will be significantly more potent than the Audi RS6 and BMW M6, both of which currently produce 552bhp.
The leaked photos also reveal straight-line performance figures. The E 63 is claimed to be capable of accelerating from 0-62mph in 3.7sec; the E 63 S is two 10ths quicker. Both are limited to a 155mph top speed, although the asterix next to that figure suggests the new car will be available with a raised top speed, should owners want one. Both models share the same claim for a 32.8mpg combined fuel economy figure, too.
Mercedes has refrained from commenting on the leaked documents, nevertheless insiders are confident the information they contain is genuine.
It is thought that the new E 63 will be lighter than the outgoing version and will be the first AMG model to use the new nine-speed automatic transmission. This second claim is backed up the aforementioned leaked document, which mentions a nine-speed MCT gearbox. It also suggests Mercedes' air body control suspension will be included, which comes as no big surprise.
AMG boss Tobias Moers has promised that these changes mean the car itself will be “not an evolution but a pure revolution - the biggest step an AMG E-Class has made”.
Speaking to Autocar, Moers revealed that the performance E-Class will be four-wheel-drive-only in all markets, but added: “Don’t worry - it will still do skids, drifts and all the stupid stuff we love.”
The car isn't due to be revealed until the Paris motor show in October, so the only images currently available have come from our spy photographers, who recently spotted a development E 63 testing in the Arctic Circle.
Order books are expected to open after the car's reveal, with first UK deliveries arriving at the start of 2017. BMW's rival model, the M5, will arrive later in 2017. That car is expected to stick with a rear-wheel-drive layout.