2023 BMW M4 CSL spy shots and video: Hardcore M4 coupe in the works

The current BMW M4 coupe (and M3 sedan) only arrived on the scene a year ago but a hotter version is already out testing.

The M4 is currently available in base and Competition grades. Previously thought to be for the next rung up the ladder, the CS, the prototypes you see here are more likely to be for a modern CSL, according to sources. Former BMW M division boss Frank van Meel also said in 2017 that new CSL models were coming, so a modern M4 CSL is not unexpected.

If you’re unfamiliar with the CSL badge, it stands for “Coupe Sport Lightweight.” The last BMW to feature the designation was the E46-generation M3, with the CSL cars built in a limited run of just 1,400 units between 2002 and 2004—such tiny numbers make it an exclusive offering, and only the most dedicated opt for the extra expense and somewhat harsher and noisier ride characteristics.