The GTS is dead, long live the CSL. BMW’s worst kept secret is finally out in the open as the former M head honcho Markus Flasch admitted earlier this month in an interview with Auto Motor und Sport that the new M4 will get the Coupe Sport Lightweight treatment. Before that happens, Auto Bild has speculatively rendered (see source link at the end) the performance coupe using the latest spy shots of camouflaged prototypes as the foundation.

Looking decisively aggressive, the M4 CSL shows off the beefier aero package and a new take on the controversial grille with Y-shaped elements on both sides of the kidneys. The large air intakes we’ve seen on test vehicles are now incorporated in the new front bumper devoid of any disguise, lending the coupe a substantially meaner fascia.

Auto Bild must know something we don’t because the dual air inlets haven’t been captured on camera by professional spy photographers as far as we can remember. We do know the M4 CSL will have a multitude of carbon fiber upgrades to shave off over 100 kilograms (220 pounds) over the regular model. The draconian diet could also include a rear seat delete, which wouldn’t be something unseen before since the M4 GTS was also a two-seat affair.

Photo by instagram.com/wilcoblok

According to sources familiar with BMW’s plans, the M4 CSL will be offered only with an automatic gearbox exclusively sending power to the rear wheels. In regards to power, the inline-six 3.0-liter turbocharged engine could be pushed towards 550 hp or approximately 10% percent more than the M4 Competition.

Even without a power bump, the CSL would be significantly faster and more agile given the significant diet said to encompass less sound insulation, among other weight-saving measures. It’s worth noting the hardcore M4 could be a rare sight since insiders have suggested only 1,000 examples will ever be made. The silver lining is a lesser CS version is expected to have a longer production run.

Of the two hotter M4 derivatives, the CSL will be out first since BMW M will unveil the amped-up coupe in 2022.

[Source: Auto Bild / YouTube] [Spy Photos by instagram.com/wilcoblok]

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