The new B5 and D5 S saloons and estates are available to order now, with first deliveries due in October. UK prices have yet to be confirmed, but the B5 saloon is priced from around £105,000 in Europe.
The headline upgrade for the B5 over the outgoing model is a power boost. Based on the M550i, the 4.4-litre twin-turbo V8 has been taken to 613bhp, up from the old car's 600bhp, with 590lb ft of torque. That translates to a 0-62mph time of 3.4sec (3.6sec for the estate) and a 205mph top speed (200mph for the estate). The extra power comes from an ECU retune and an improved cooling system with enlarged intercoolers.
The D5 S also benefits from a power upgrade, rising from 322bhp to 342bhp partly thanks to the installation of a 48V mild-hybrid system. Torque is up from 516lb ft to 538lb ft, too. Two-tenths are shaved off the 0-62mph time, down to 4.8sec, while a 171mph top speed results.
The B5 and D5 S again feature the same range of chassis upgrades as before. This includes electronically controlled dampers, stiffer springs and upgraded brakes, with four-piston fixed calipers at the front and single-piston floating calipers at the rear.
The B5 features an electromechanical rear-wheel steering system, aimed at improving around-town manoeuvrability while also aiding high-speed stability. Touring models retain the self-levelling rear axle air suspension as the standard 5 Series.
The aesthetic changes reflect that of the 2020 5 Series, too, with front intakes enlarged by 40% to improve cooling, redesigned lights front and rear and a new rear bumper. The trademark multi-spoke Alpina wheels are retained, alongside quad tailpipes for both variants.
Upgrades to the interior include a hand-stitched leather wheel and numbered plaque on the dashboard. The upgraded infotainment system features, as does a 12.3in digital instrument display with bespoke Alpina graphics.