Like the sporty Alpina B5 wagon prototype spotted in August, this development vehicle has the same mismatched alloy wheels at the front and back, while the front and rear bumpers also sport a similar design.
In typical Alpina fashion, visual upgrades will be relatively subtle, with a new front spoiler, rear bumper, larger alloy wheels and quad tailpipes sticking out at the rear.
Under the bonnet, the B5 is expected to feature an uprated version of the company’s 4.4-litre V8 producing around 580 horsepower (432.5kW).
The most powerful version of the new sixth-generation 5 Series - at least until the M5 is launched - is the M550i xDrive, which packs a 340kW/650Nm version of the 4.4-litre turbocharged V8.
With that combination, the M550i is capable of sprinting from 0-100km/h in just 4.0 seconds flat.
While the Alpina B5 is likely to be rear-wheel drive, expect it to post similar performance times thanks to its healthy power advantage.
It’s expected the Alpina B5 and diesel-powered D5 will be revealed around the same time as the new M5, likely to be mid- to late-2017.
Click the photos tab for more images of the 2017 Alpina B5 sedan.
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