Bentley has revealed details of the new Continental GT Speed – a high-performance grand tourer that the marque says is the most dynamic road car in its 101-year history.

A retuned version of its famous W12 engine now produces a massive 650bhp – a 24bhp increase and maintains the 664lb ft torque figure. Sent to the road via an eight-speed automatic gearbox and all-wheel-drive, that’s good enough to get the GT Speed from 0-62mph in just 3.5 seconds and see it run on to a top speed of 208mph.

The transmission is the same as in the standard car but has been retuned specifically for this model with shifts up to twice as fast as the standard models and a new rear-biased torque delivery in Sport drive mode.

The Sport mode also adapts settings for a new electronic rear limited slip differential – the first time Bentley has fitted one. This allows for more adjustability, better turn in and improved straight-line performance, according to Bentley’s engineers.

Also new for the Continental GT Speed is a version of the four-wheel-steering system from the Flying Spur which sees the rear wheels turn in the opposite direction to the fronts at low to medium speeds to reduce the turning circle and in the same direction at higher speeds to improve stability.

Combined with the eLSD and retuned stability and traction control, Bentley says the chassis updates provide a noticable character shift from other Continentals and offer a level of agility “unlike any other Bentley road car”.

Helping rein in all that power and performance are new 10-piston carbon ceramic brakes hidden behind model-specific 22-inch alloys.

The Continental GT Speed features a host of other cosmetic upgrades to distinguish it from regular Continental GTs. Dark tinting to the radiator and lower bumper grilles and unique sills mark it out, as do discreet chrome Speed badges on the front wings. Inside, a unique two-tone leather and Alcantara finish is standard, as is the diamond-on-diamond upholstery and headrests embroidered with the Speed logo, which also appears on the dashboard.

As for cost, Bentley hasn’t said, but with the regular V8 Continental GT starting at around £160,000 if you have to ask, assume you can’t afford it.