Infiniti - that's the luxury arm of Nissan, for those unaware - has just revealed the Q50 'Eau Rouge' concept. It's packing a full 560bhp, and is gunning straight for the BMW M5. At least it would be if it was real.

You'll remember the Eau Rouge. We first saw it as a design concept, shown at the Detroit show in January and named after the famously puckering corner at Spa. Infiniti was schtum on powertrain details then, but has shown its hand now. And it's quite a hand.

See, the Q50 Eau Rouge uses the same hand-built 3.8-litre twin turbo V6 lifted straight from the current Nissan GT-R, but here featuring an 'Infiniti Performance ECU'. It doesn't use the GT-R's four-wheel-drive, but an Infiniti 4WD system ' like the one on the FX, for example ' with a 50:50 torque split front and rear.

Speaking of torque, the Eau Rouge serves up a generous 600Nm, channelled through a 7spd automatic gearbox (no dual clutch frippery here) to record a 0-100km/h time of 'under four seconds' and estimated top speed of 290km/h. Considering the GT-R manages the 100km/h sprint in around three seconds, Infiniti could be playing a little modest here'

Both front and rear tracks have been increased over the standard Q50 by 20mm, there are simply massive brakes, 20-inch lightweight forged aluminium alloys, a bespoke carbonfibre front bumper, a bonnet with cooling vents, wider arches. Oh, and a one-piece carbon fibre rear bumper with a very cool touch: it incorporates the rear LED brake light from the Red Bull Formula One car.

However, this Q50 Eau Rouge concept wasn't actually built in conjunction with Red Bull, nor indeed Infiniti's new 'Director of Performance' Sebastian Vettel. But we're told Infiniti is desperate to build this thing, and if Mr Vettel's talents were to be deployed anywhere in the company'

Obviously, it being a concept means there's no production schedule, but if the Q50 Eau Rouge did get built, we'd expect it to cost just under ' or around the same price as a BMW M5. Reckon this could hold its own against the big Beemer? Or indeed the Audi RS6 or Mercedes E63 AMG?