Updated bahn-storming limousine is now capable of 330km/h if you can find a road long enough, as if the previous one wasn't bonkers already.

Alpina Automobiles has taken the wraps off the updated 2020 B7 xDrive, based on the facelifted BMW 7 Series limousine.

Like the vehicle on which it's based, the B7 gets a host of design revisions including new lights and bumpers, along with a revised interior incorporating the latest BMW driver assistance and infotainment systems.

Under the skin, changes have been made in the engine bay to improve responsiveness and enhance power delivery across the rev range.

The 4.4-litre twin-turbo V8 puts out the same 600hp (447kW) and 590lb-ft (800Nm), though it features new 54mm impeller strapped onto the exhaust side of the turbochargers (up from 50mm).

Combined with new intercoolers specific to the B7 and revised engine management software, the B7 xDrive offers a wider peak torque band (2000-5000rpm, previously 3000-5000rpm).

The company says the changes help the B7 shave 0.1 seconds off its 0-60mph (0-97km/h) time – now 3.5 seconds instead of 3.6 – while top speed is now rated at an eye-watering 205mph (330km/h), up from 194mph (312km/h).

Shifting gears is an updated ZF-sourced eight-speed sports automatic transmission that has been adapted for the new B7's powertrain, sending that grunt to all four wheels.

Filling the arches are 20-inch alloys as standard, with 21-inch units available as an option. The rims are shod in Michelin performance tyres (255/40 front and 295/35 rear for the 20-inch wheels) that forego run-flat technology for improved ride comfort.

Behind the wheels is a revised braking system that employs brake-by-wire technology, featuring four-piston calipers at the front with floating units at the rear.

The front discs measure 15.55 x 1.42 inches (395 x 36mm), while the rears are larger than before at 15.67 x 1.10 inches (398 x 27.94mm).

Like the wider Alpina range there's still a plethora of cost options available to those who want to further customise their vehicle, from quilted nappa leather upholstery and rear entertainment systems to heated, ventilated and power-adjustable rear seats.

Australia

Speaking with CarAdvice, Alpina's local division said: "The Alpina B7 timing is yet to be confirmed by Alpina Australia".

Currently, the pre-facelift model retails for a hefty $369,720 before on-road costs, and it only drives the rear wheels.