An observant CARtoday.com reader has photographed what appears to be a prototype of BMW's eagerly anticipated V10-powered M6.

A CARtoday.com reader has photographed what appears to be a prototype of BMW's eagerly anticipated V10-powered M6. The exact location where the picture was taken is unknown.

Finished in shiny black paintwork, the car (pictured right) has characteristic, flowing tension lines and unusual stretched, but classical proportions. The passenger space is set far back and has a very low roofline and outlined style elements at the front side panels loosens up the car's silhouette. When comparing the picture to earlier spy shots of the M6 (shown below) the prototype shows similarly-proportioned (about 19-inch?) wheels and equally-elaborate front and rear spoilers.

More importantly, the M6 will be powered by the same naturally-aspirated, forty-valve five-litre V10 powerplant that will début in the 5 Series flagship, the M5.

With about 375 kW and 700 N.m of torque on offer, the M6 should be able to sprint from zero to 100 km/h in around five seconds. Top speed will be limited to 250 km/h, however.

The M6's suspension will be similar to that of the M5, much lower and stiffer than that of the 645i, and there is likely to be the option of six-speed manual or six-speed auto transmission.

As in the new 5- and 7-Series, all functions required for driving the car are located directly on or around the steering wheel. The M6 will also feature a host of BMW's bells and whistles: dynamic drive control (DDC), dynamic stability control (DSC) and dynamic traction control (DTC) are standard.

As an option, the 6-Series is also available with BMW's Dynamic Drive suspension, which helps compensate body sway in a bend, as well as BMW's Active Steering, which provides a more direct steering ratio at low speeds, together with more indirect steering at high speeds.

Runflat tyres are standard, and adaptive headlights will be available as an option. Lightweight, thanks to the use of aluminium, steel and synthetic materials, the overall weight of the car is approximately 1 600 kg, with axle load distribution close to 50:50.

But it won't be the quickest 6 Series on offer... A lightweight M6 CSL with carbon-fibre panels and an extra bit of horsepower is also on its way, though not for at least three years. The M6 should be launched next year with convertible versions to follow.