Under the hood is a 4.4-liter V8, which produces 600 hp (447 kW) and a whopping 590 ft-lb (800 Nm) of torque. That's the same amount of power as the limited edition M5 30 Jahre produced, but 100 Nm more torque. It's no surprise, then, the Alpina handles the 0-62 mph (100 km/h) sprint in just 4.1 seconds, which is 0.1 seconds quicker than the M5 Competition Package.
Part of the reason the Alpina's extra power doesn't translate to a massive improvement in sprint time is down to the gearbox, with the B5 Biturbo eschewing the M5's dual clutch gearbox for a more conventional eight-speed automatic. We also suspect the car might battle to channel all its torque through the rear wheels off the line, but once you're on the move that huge torque figure isn't such a problem, evidenced by the B5's 204 mph (328 km/h) top speed.
It might be incredibly powerful but the Alpina B5 is actually reasonably economical, with a fuel efficiency figure of 9.5 L/100 km (25 mpg) and emissions numbers of 221 g/km of CO2.
If you're the sort of person who really wants to hear your V8, there's a titanium Akrapovic exhaust available. As well as creating a better soundtrack, the system saves 37 lb (17 kg) compared to the standard setup.
There's more to the B5 than just a big, powerful engine. A limited-slip differential is fitted as standard, and Alpina's adaptive sports suspension has been upgraded to include active dampers and active roll stabilization. That said, Alpina's cars have traditionally placed a greater focus on comfort than outright trackday performance, so don't expect the B5 to shred a circuit like a standard M5.
On the inside, there's full merino leather upholstery and a leather trimmed dash, while Alpina-specific piano black trim provides a point of difference. As is typical of Alpina's work, the car's exterior is topped off with a subtle bodykit.
So, how much will this 204 mph BMW cost you? Well, if you're keen on a sedan you're up for €108,600 (approx. US$115,370). If you want your speed in estate form the Alpina will set you back €111,900 (approx. US$118,880).