The current BMW 3 Series is on its way out. That means the M3 along with it. But before it’s gone, BMW appears to be working on a more hardcore version to serve as the performance sedan’s swan song.

Pictured fueling up in between test runs at the Nürburgring is what appears to be a new M3 CS. And while part of its bodywork is wrapped up in camouflage, it’s not hard to imagine what’s underneath.

That’s because BMW already offers a CS version of the M3’s coupe counterpart, the M4. So what we’re likely looking at here is the same treatment applied to the four-door F80 model.

That should mean a 3.0-liter twin-turbo straight six beefed up by 29 horsepower and 37 lb-ft of torque over the standard M4 to a good 454 hp and 442 lb-ft. A lightweight aero kit also looks to be part of the package, with upgraded suspension, rolling stock, and brakes to go with it.

The paparazzi at CarPix anticipate the new M3 CS to be unveiled at the Geneva show next March, but BMW doesn’t usually wait for a major show to present its latest metal – so don’t be surprised to see the thing surface long before then.

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