Historically among BMWs, the CSL suffix has stood for Coupé Sport Leichtbau, or “Lightweight Sport Coupe.” The name first appeared on the E9 3.0 CSL and the famous E9 CSL–based “Batmobile” race car. BMW later offered an extra-hot E46 M3 CSL, too. It’s one of the most revered nameplates in company history, but somehow we’ve had to wait nearly two decades for its resurrection in the form of the 2023 M4 CSL.
What a return. In the CSL transformation, BMW shaved 240 pounds from the M4, including 46 alone by deleting the rear seats. Additional alterations include a titanium rear silencer, M carbon-ceramic brakes, plenty of badging, and lighter forged wheels, springs, and struts. Unique engine and transmission mounts, reworked suspension tuning, and powertrain upgrades are on the list, too.…