Which 4-Series model is more expensive, less zany in looks, rarer and at least on paper, potentially faster than the M4? Why the Alpina B4 Bi-Turbo, of course. Set to make its UK launch at next week’s Goodwood Festival of Speed, the B4 is available as a Coupe for £58,950 or as a hardtop convertible for £62,950.

This means Alpina’s B4 Bi-Turbo Coupe is £2,300 more expensive than the new M4 Coupe (£56,650) with the Convertible carrying a £2,205 premium over the drop-top M4 (£60,745).

While based on the 435i, Alpina says a team of 50 development engineers worked with specialist suppliers to “enhance the engine, gearbox, cooling system, body structure, wheels, tyres, aerodynamics, steering, suspension and interior”.

In the B4, the revised 3.0-liter twin-turbo straight six produces 404hp (410PS) and 600 Nm (442 lb-ft) of torque, up from the 435i’s 306PS (302hp) and 400Nm (295 lb-ft).

The Coupe shoots to 100 km/h(62 mph) from zero in 4.2 seconds and has a top speed of 305 km/h (190 mph), with the Convertible doing the same in 4.5 sec and topping out at 301km/h (187mph). In comparison, the M4 Coupe hits 100km/h in 4.3 seconds with a manual gearbox and in 4.1 seconds with the dual-clutch transmission, with both reaching an electronically limited top-speed of 250km/h (155mph).

While not available in right-hand drive markets, the Alpina B4 Bi-Turbo Coupe with all-wheel drive (xDrive ) is even faster hitting 100km/h in four seconds flat.

Speaking about the new B4, Alpina GB sales manager Matthew Stripling said:

“ALPINA customers value the finely-honed feel of a bespoke car and the easily accessible performance that comes with substantial torque available at almost any engine speed. We are not trying to compete with cars that must also perform well on a track. An ALPINA is often described as ‘the best performance car for the real world’ and that’s something we are very proud of.”

In the UK, the B4 has a long list of standard features that include, an eight-speed automatic gearbox, Adaptive M Sport Suspension, leather upholstery, electrically adjustable heated sports seats, climate control, Bi-Xenon headlights, aero kit and 20-inch wheels.

Furthermore, Alpina offers all other BMW options, including those from its Individual program.

By John Halas

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