330km/h Alpina B7 breaks cover

Alpina has announced it will offer an updated version of its Alpina B7 Bi-Turbo xDrive based on the recently facelifted BMW 7 Series.

Although it features the same full-size kidney grilles as the latest BMW limousine, Alpina designers have subtly restyled its take on the world's fastest limo with reprofiled front and rear bumpers.

Under the bonnet the old car's monstrous twin-turbo 4.4-litre V8 carries over and produces an identical 447kW and 800Nm of torque peak.

However, thanks to some expert tinkering by the famous BMW tuner, the mighty Alpina B7 Bi-Turbo can now hit 60mph (97km/h) in just 3.5 seconds -- 0.1sec quicker than before.

Perhaps even more impressive if you live near a German autobahn, or own your own private runway, the big Alpina B7 can now top out at 330km/h -- about 19km/h faster than the car it replaces.

Both performance gains are said to be from new software for the ZF-sourced eight-speed automatic transmission and a new stainless steel sports exhaust that slashes weight and reduces back pressure.

The xDrive all-wheel drive system has a new map that's claimed to have boosted agility by allowing larger drift angles.

To cope with the added performance Alpina has revised the brake system, adding larger discs front and rear and introducing new four-piston front callipers.

As part of the mid-life tweaks, the B7 also features a new Michelin tyre and the option of a 21-inch wheel.

Inside, the big Alpina sedan scores new finishes, colours, trims, premium leathers and a new design for the virtual instrument panel.

Improving refinement, the Porsche Panamera Turbo rival also now comes with thicker side and rear window glass.

The 2019 B7 is set to make its debut at the Geneva motor show next month, but local release timing and pricing are not yet clear. The B7 Bi-Turbo super-limo current sells for a cool $369,720 (plus on-road costs).