Alpina lays its hands on the BMW 4 Series Convertible

The Alpina B4 Bi-Turbo Convertible is characterised by short overhangs, precise, long drawn shoulder lines, a wide rear and a charming metal folding roof. The sporty and purposeful design of the front spoiler is dictated by functional air intakes and operates in conjunction with the rear spoiler to improve stability at high speeds.

Functional aerodynamics, signature 20-inch Alpina classic wheels and two elliptical double tailpipes are hallmarks of the Alpina design philosophy and lend a particularly elegant presence.

The shape of the roof line when closed differs from the Coupe significantly due to the steeper rake of the rear windscreen, the flat boot lid and subtle rear spoiler.

Like the name suggests, the 2,979cc straight-six engine in the Alpina B4 Bi-Turbo is equipped with two turbochargers to deliver 410bhp and a maximum torque of 600Nm.

In combination with the excellent ZF eight-speed transmission, the B4 Bi-Turbo Convertible accelerates from zero to 100km/h in 4.5 seconds on its way to a top speed in excess of 300km/h.

Braking power is provided by 18-inch high performance brake system with 370mm discs at the front and 345mm discs at the rear. Blue painted aluminium callipers with Alpina lettering, in conjunction with high performance pads, ensure fading stability and optimal pedal feedback.

The stainless steel exhaust system was developed in collaboration with Akrapovic and is 7.5kg lighter in comparison to its predecessor. The resonant, sporty sound of the exhaust system is controlled by an intelligent exhaust valve. In Sport Mode, the valve is permanently open and the B4 Bi-Turbo thrills with its distinctive aural character under hard acceleration.