Performance diesel SUV spied alongside mystery X3 prototype

BMW X3 prototype believed to be the upcoming Alpina XD3 has been spied this week in its home of Germany.

Spotted near another camouflaged X3, the Alpina is distinguished by its front bumper design (below), which is closely related to those on other models across the tuning company's range.

Top: Alpina XD3, Bottom: BMW X3 prototype

Unlike to BMW's in-house performance versions of the X3, the Alpina XD3 uses diesel power - twin-turbo-diesel, to be exact.

Details of the new car's powertrain are yet to be detailed but the outgoing version, based on the previous-gen X3, utilises a 3.0-litre bi-turbo six-cylinder diesel engine developing a healthy 257kW of power and 700Nm of torque - the latter available from just 1500rpm.

The current car sprints from 0-100km/h in 4.9 seconds, on its way to a top speed of 251km/h. Expect the new version to improve on both figures.

It's unknown at this stage whether the new Alpina XD3 will make it to Australia, considering the local arm doesn't import any current diesel models. However, Australia's thirst for performance SUVs might mean Alpina will bring the car Down Under to provide a more fuel-efficient alternative to the petrol-powered X3 M40i.

Meanwhile, the blue X3 pre-production vehicle (above) is a thing of mystery. Put simply, we aren't quite sure what it is. An X3 M? Maybe - the large wheel and tyre package is similar to that seen on previous X3 M prototypes, however, this car has dual exhaust tips at the rear where the M prototypes have sported a quad-tip setup.

There are also massive brakes hiding behind the 20-something-inch rims, with blue calipers that are a signature BMW M feature.

Another distinguishing feature are the additional intakes beneath the LED foglights in the front bumper - which are fake in the M40i.

Stay tuned to CarAdvice for updates in the coming months. Click the photos tab for more images.