A prototype BMW M4 has been spotted in testing, featuring a fixed rear wing and unique exhaust design.
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A vehicle thought to be a 2021 BMW M4 GTS has been spied driving on a motorway in Germany, revealing some unique design features.

The photos, originally posted on Instagram by @diddyf30, show a fixed rear spoiler which suggests the car may be a GTS version of the upcoming 2021 BMW M4, as seen on the previous limited-edition BMW M4 GTS.

More curiously, however, is the diagonally-stacked centre exhaust tips – not entirely dissimilar to the signature exhaust tips found on performance Lexus models.

The upcoming BMW M4 will be powered by a 3.0-litre twin-turbo six-cylinder producing 353kW/600Nm, available with either an auto or manual transmission driving the rear wheels.

In the M4 Competition power will increase by around 25kW, and will be paired exclusively with an eight-speed torque-converter automatic and all-wheel drive.

While no details have emerged for the BMW M4 GTS, if prior models are anything to go by, a power increase could see the performance car pushing more than 400kW.