BMW’s M division has long been known for developing performance-tuned versions of the automaker’s standard road cars, and over the decades, machines like the M3 and M5 have earned a reputation for expertly achieving a difficult balance between track prowess and daily drivability. But every once in a while, BMW lets the M division off of the leash to build cars like the M4 CSL, where that balance takes a back seat to outright performance.
The first Competition Sport Lightweight (CSL) model dates back to 1972 and the introduction of the 3.0 CSL, a limited-production homologation special that was created to make the svelte coupe eligible to compete in the European Touring Car Championship. The 3.0 CSL race car took home the series title the following year.
More than three decades went by before BMW decided to revisit the badge, but the 2003 M3 CSL made up for lost time. A hardcore iteration of an already-beloved sports coupe, the limited-production CSL dropped more than 200 pounds due to the liberal use of lightweight materials and by ditching some of the standard M3’s creature comforts, while grip and power were increased to help push the car’s athleticism even further.
The M division has produced a number of special-edition M cars in the years since, but none have worn that coveted CSL badge—until now. Limited to just 1,000 examples worldwide, the M4 CSL follows the template established by its predecessors, dropping 240 pounds versus the M4 Competition thanks to the use of carbon fiber for the hood, roof and rear decklid, along with the removal of the rear seats and some sound deadening material. Weight was also lopped off by utilizing components like unique carbon-bucket race seats, titanium-exhaust-system hardware and model-exclusive forged wheels. The combined efforts bring the M4’s curb weight down to a more palatable 3,640 pounds. The alloys come wrapped in ultra-sticky Michelin Pilot Sport Cup 2 R road-legal track rubber as standard fitment, but more street-friendly Pilot Sport 4S summer tires are also available as a no-cost option.
The enhanced grip is complemented by a host of model-specific chassis tweaks that include stiffer springs and beefed-up sway bars, revised adaptive dampers, firmer engine and transmission mounts and a new aluminum strut brace in the engine bay. The CSL’s center of gravity is also brought down thanks to a ride height that’s been lowered by 0.3 inches compared to the M4 Competition.
There’s more power on tap as well: While the 3.0-liter twin-turbocharged inline six engine’s torque figure remains unchanged from that of the M4 Competition, coming in at 479 ft lbs, increased boost pressure and recalibrated engine software net the CSL an additional 40 ponies for a total of 543 hp. That grunt is sent exclusively to the rear wheels through an eight-speed automatic gearbox, a combination that results in a zero-to-60 mph sprint of 3.6 seconds on the way to a top speed of 191 mph.
The M4 CSL also looks the part of a track-ready sports car. Although the M4’s polarizing front-end design remains, the kidney grilles are bespoke to the CSL and are engineered to optimize airflow to the radiators. And thanks to the new front splitter, hood scoops, red accent striping and the integrated spoiler on the rear decklid that pays homage to the M3 CSL while delivering additional downforce at speed, the overall look is significantly more aggressive and compelling, yet not outlandish for a motorsport-inspired machine like this.
It’s a similar story inside, where the M4’s standard sport seats have been replaced by fixed-back carbon race buckets that were developed specifically for the CSL. Fore and aft adjustments are made by way of a lever at the front of the seats, but height adjustments require a tool kit. The seats alone save 53 pounds over the power-adjustable and heated carbon-backed seats offered on the M4 Competition, but as with the tires, buyers can opt for the easier-to-live-with option at no additional charge.
Once we get settled in behind the wheel, the track-ready seats immediately make sense. A press of the ignition button brings the engine to life with a new sense of authority due to the revised exhaust system and reduced sound deadening, while the hunkered-down seating position and exposed carbon fiber on the center console make the CSL’s mission clear: This is BMW’s answer to the Porsche 911 GT3, a track-focused monster with a license plate.
Despite its raison d’être, the M4 CSL is actually pretty agreeable when conscripted for more mundane driving. Sure, a bit more road noise creeps into the cabin and very few will be able to gracefully extract themselves from those aggressively bolstered carbon buckets, but the seats are fairly comfortable once you’re situated. BMW’s habit of offering a daunting level of performance adjustments works to its benefit here; since everything from the shift firmness and exhaust volume to brake-pedal response and steering effort can be electronically altered. Setting all of the adjustments to their softest options yields a car as easy to drive around town as a garden-variety M4, albeit with a noticeably stiffer suspension tune.
Ultimately, though, every moment spent puttering around just seems like downtime between lapping sessions. Although we weren’t offered a chance to test the M4 CSL on a track, an extended jaunt up Highway 74 in Palm Desert, Calif., provided a glimpse of what this car was really made to do.
While the electrically assisted variable-ratio steering remains low on meaningful feedback, and the effort is still a bit too light for our tastes—even in Sport mode—turn-in is near-instantaneous and precise thanks to tenacious mechanical grip and a buttoned-down chassis with plenty of negative camber dialed in. Held firmly in place by those gnarly race buckets, we press harder with each successive corner and dip further into the loud pedal every time the road straightens out. As with the M4 Competition, there’s a sense that BMW is being conservative with the CSL’s power rating, and we wouldn’t be surprised if independent testing revealed that there’s up to another 60 hp that the automaker forgot to mention. But hey, we’re not complaining, especially when there’s plenty of fade-free stopping power at the ready via the standard carbon-ceramic brakes.
Of course, at a starting price of $139,900—nearly double the base MSRP of an M4 Competition—there are some inherent expectations. Initial impressions suggest that the CSL delivers on its promises, but public roads can only tell part of the story when a vehicle has its performance limits set this high. For the fortunate few who manage to get their hands on one of these—a rewarding endeavor in and of itself—every indication points to a machine that has many more thrills to offer when it’s set loose on a closed course.
Click here for more photos of the 2023 BMW M4 CSL.