While it may look like an ordinary 2014 BMW 4-Series, some signature Alpina elements reveal its true identity. The biggest giveaway are the quad-exhaust tips, which match the units on the 2013 BMW Alpina B3 Biturbo (based on the BMW 3-Series sedan).
The prototype, which is even marked as a “Werkstestwagen,” also wears Alpina’s popular multi-spoke wheels, measuring 20 inches across. The final giveaway are the blue-painted brake calipers, which even look to be marked with Alpina branding.
Like its latest B3 Biturbo, Alpina’s new B4 Biturbo will most likely come to market with a twin-turbocharged version of BMW’s 3.0-liter straight-six engine found in the 435i coupe. In stock form this engine rates at 300 horsepower and 300 pound-feet of torque, but with Alpina’s tuning expect output to be dialed up to 410 horsepower and 442 pound-feet of torque.
That should see the B4 Biturbo sprint to 60 mph from rest in around 4.0 seconds and reach a top speed of close to 190 mph.
Other performance modifications should include discrete changes to the bumpers, adjustable suspension and a tweaked version of the ZF eight-speed automatic fitted to the regular 4-Series range. An all-wheel-drive B4 Biturbo should also be launched further down the track in addition to a successor to the previous B3 GT3 race car.