The new 911 GT2 RS has to be Porsche’s worst kept secret. But not a lot can prepare you for a passenger seat blast in the maddest and most-powerful 911 ever built.

This is what we know: the new GT2 RS will have ‘in excess’ of 650bhp and 553lb ft, via a heavily revised 3.8-litre twin turbo flat-six pinched from the 911 Turbo S.

There’s water-injection intercooling, new internals, unique turbochargers, and more. It bins the Turbo’s four-wheel drive (driving only its rear wheels), adds a seven-speed PDK gearbox, and raids the GT department’s parts bin for all the best bits. It also adds some new ones for good measure.

Note those headline power and torque figures; Porsche is currently willing to communicate they are conservative. Each comes with the ‘greater than’ symbol, suggesting the final figures will be significantly more. Just think about that for a second.

It will, in the words of GT department boss Andreas Preuninger, shout “I’m the alpha animal”. That’s very deliberate, for the GT2 RS is a 911 that appeals to a rather different customer than other models. The prototype here might look like a GT3 RS with cladding, because that’s what it is. But visually the production car promises to be even more unhinged, with a huge front splitter, massive rear diffuser and plenty of exposed carbonfibre.

That’ll include two NACA ducts on the bonnet that feed air to cool the standard carbon-ceramic brakes. Choose the optional Weissach pack (like a Porsche 918 Spyder gets) and you’ll add titanium, magnesium and more carbon into the mix, and shave 30kg off the anticipated sub-1,500kg kerb weight.

Preuninger says the GT2 RS “is all about competition”. By that, he means pummeling them into submission around that track. To better its rivals around the Nürburgring it’s got rose-jointed suspension, with upside down race dampers and spring rates equal to a Cup car’s ‘Ring setup. Even so, it rides with remarkable civility on the roads around Weissach.

And that lap time? It’ll need to start with a six if it’s to better the Lamborghini Huracan Performante’s recent efforts, which given the 911 GT3’s 7min 12sec, with a paltry 493bhp, isn’t so difficult to believe.

Certainly not from where we’re sitting. The 3.8-litre engine’s force is brutal, and we mean 918 Spyder ferocious. Forget any talk that turbocharging robs an engine of sound, too. Sat in the red Alcantara interior (a reverential, eye-straining nod to the design optioned by 60 per cent of previous-gen 997 GT2 RS owners) you’re not just physically stimulated by the engine’s ferocity and the chassis’ grip, but aurally, too.

The expectation is a top speed in excess of 211mph, a 0-62mph under three seconds and 0-124mph comfortably under nine. Yet – says Preuninger – it’ll have all the agility and poise of a 911 GT3 RS.

Job well done then? We’ll only know for sure when we’ve actually driven it. But on early evidence from the wrong seat, it looks to be a job very well done.