By now, you have probably heard that the upcoming 2014 BMW M3 in both four- and two-door formats will do away with the current model’s atmospheric 4.0-liter V8 and gain a turbocharged six-cylinder engine.

Most seem to agree that the most likely candidate is an M Division modified version of one of BMW‘s 3.0-liter straight-six units with either two or three turbos.

However, there are some rumors circulating around the net that BMW is developing a new force-fed V6 engine for its next M3 models. The speculation is based on a recent design filling for a twin-turbocharged V6 made by the Bavarian company at the German patent office. BMW has not commented on the matter.

We’ve already shared with you a batch of spy shots of the 2014 BMW M3 sedan, but today, the crew over at Bimmerpost got their hands on a scoop video showing the sports saloon on the road.

What’s interesting about this clip is that we get the chance to hear the sound of the new M3’s engine. Needless to say, being a prototype, the engine and the exhaust system are not yet calibrated. Watch the video below and tell us what you think is lurking under the hood of the new M3.

Story references: Bimmerpost

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