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BMW M4 CSL: High-end racer for everyday driving

As part of its 50th birthday celebrations, BMW is producing a very special limited-edition model -- the new 2023 543-hp BMW M4 CSL. It mixes old-school track enthusiasm with innovative technology to create a formidable racer for everyday driving. With its next-level power, intelligent lightweight design, two-seater configuration, model-specific chassis upgrades, and bad-to-the-bone looks, it's the closest a BMW production car has ever gotten to one of the brand's official race cars.

The M4 CSL takes just 3.6 sec to reach the 60-mph mark from rest and can sprint to 120 mph from a standing start in just 10.5 sec. Top speed is limited to 191 mph. The car will be limited to 1,000 units.

BMW says the M4 CSL is built around two core features: a power hike of 40 hp over the current BMW M4 Competition and a 240-lb reduction in weight. The genes the new BMW M4 CSL shares with its competition-spec sibling, the BMW M4 GT3, are also reflected in its performance attributes. In test runs on the Nurburgring's Nordschleife circuit, which represent the ultimate yardstick for brand-typical dynamics like agility and handling precision for all BMW M cars, the M4 CSL posted a lap time of 7:20.2 -- the fastest time ever for a series-production BMW.

High-revving characteristics and latest-generation M Twin Power Turbo technology make the inline 6-cylinder power unit from the BMW M4 Competition the perfect starting point for the high-performance engine in the most powerful road-legal M4 variant ever made. Detail modifications for the new BMW M4 CSL produce a maximum output of 543 hp at 6,250 rpm. Peak torque of 479 lb-ft is on tap from just 2,750 rpm and sustained all the way up to 5,950 rpm.

The torque produced by the S58 engine is sent to the rear wheels via an eight-speed M Steptronic transmission with Drivelogic. The M-specific version of this automatic transmission features ratios precisely attuned to the engine's characteristics and an extremely sharp shift action matched to the engine's performance. This enables gear changes to be performed even faster than in the M4 Competition. Manual shifts with sequential gear selection can be performed using either the selector lever or the carbon-fiber shift paddles on the steering wheel.

Providing the ideal basis for the new BMW M4 CSL's chassis technology is the combination of a double-joint spring strut front axle and five-link rear axle, both in M specification. This design principle was developed specifically for the high-performance sports cars in this model range. Also standard is the Adaptive M Suspension with electronically controlled dampers, electromechanical M Servotronic steering with variable ratio, and an M-­specific version of the integrated braking system.

The M-specific components also include a cylinder head with 3D­-printed core. This additive manufacturing process enables geometric forms to be created that are beyond the capability of conventional metal casting techniques. As a result, the coolant duct routing could be optimized while also reducing its weight.

Intelligent lightweight design was a fundamental strategy in the development of the new BMW M4 CSL. BMW says conventional components for the exterior and interior, powertrain, and chassis were replaced with lightweight model-specific alternatives. Fitting M Carbon full bucket seats alone reduced weight by 53 lb, while a further 46 lb were saved by removing the rear seats and seat belts and integrating a partition between the cabin and luggage compartment. Chassis alterations, including the addition of standard lightweight M Carbon ceramic brakes and forged light-alloy wheels, springs, and struts, reduced weight by another 46 lb. Switching to ultra-lightweight sound insulation and reducing the amount used saved another 33 lb. The use of carbon fiber reinforced plastic (CFRP) components on the outside and inside of the M4 CSL saves an additional 24 lb. A titanium rear silencer cuts more than 9 lb from the weight of the exhaust system. Detail modifications shave another 8 lb from areas including the BMW kidney grille, rear lights, floor mats, and automatic climate control.

The forged M light-alloy wheels in cross-spoke design have been designed exclusively for the new BMW M4 CSL. Minimized weight and a distinctive appearance are the standout characteristics of the 19-in. front and 20-in. rear matte black wheels. The precise arrangement of the super-slim spokes gives the wheels exceptional rigidity. Their design also helps to reduce unsprung mass, further enhancing the agile driving characteristics of the CSL. M Carbon ceramic brakes are standard equipment on the new M4 CSL and are 31.5 lb lighter than the M Compound brakes. Their red-painted calipers clamp down hard on 15.7-in. front and 15-in. rear discs.

The new BMW M4 CSL can also be ordered with the traditional high-performance tires from the M4 Competition in the same sizes, at no cost. These tires enable highly dynamic driving while enhancing comfort in everyday use and on long journeys.

The roof panel on the BMW M4 CSL, as on the M4 Competition, is made from CFRP. The use of this lightweight yet hugely robust high-tech material at the highest point of the body reduces the vehicle's overall weight while lowering its center of gravity, which in turn enhances agility and cornering dynamics. Carbon fiber is also used for the hood and trunk lid.

The red accents and exposed carbon-fiber stand in dynamic contrast with the optional Frozen Brooklyn Grey metallic exterior paint finish to create a high-impact visual statement. Alternatively, customers can also specify their new BMW M4 CSL in standard Alpine White or Black Sapphire metallic. Standard BMW M 50 Years emblems for the hood, trunk lid, and wheel center caps mark the 50th anniversary of BMW M GmbH. Their design recalls the blue/violet/red logo first seen on the BMW Motorsport GmbH racing cars in 1973. CFRP is also used for the splitter fitted to the lower edge of the front apron to generate additional downforce, and the inserts in the air curtains at its outer edges.

The BMW Laserlight headlights bring a touch of the racetrack to the front of the car, with the angular daytime running lights illuminating in yellow rather than white, evoking the look of GT racing cars. The rear lights feature innovative technology making its debut in a series-produced car. While all the light functions use LEDs, the glass covers have intricate light threads woven into them that are illuminated using laser technology.

Inside, it's all about that racing feel. The lightweight coupe only has seats for the driver and one passenger, but these are no ordinary seats. The M Carbon full bucket seats were developed exclusively for the BMW M4 CSL with the focus on the demands of track driving. Their carbon fiber structure and lack of comfort features such as heating, lumbar support, and power adjustment reduce weight by 53 lb compared with the standard seats fitted in the BMW M4 Competition.

With their pronounced bolsters, the M Carbon full bucket seats offer an extremely high level of lateral support through corners. The backrest angle is fixed, and the seat height can only be adjusted in a workshop using a three-stage screw linkage. Fore and aft adjustments are made manually using a lever on the front edge of the seat. The head restraints can be disassembled for track use when the driver and passenger are wearing helmets.

The seating surfaces and backrests of the M Carbon full bucket seats are trimmed in black Merino leather. The outer surfaces of the backrests and head restraints have red Alcantara inserts. Contrast stitching in the colors of BMW M GmbH adorn both the seat bolsters and the seat belts.

Heated M Carbon bucket seats with full power adjustment are available as a no-cost option. These seats are 21 lb lighter than the standard seats in the BMW M4 Competition and combine track functionality and lightweight design with a much higher level of comfort and adjustability over long journeys.

The stowage area behind the seats for the driver and co-driver provides space for two helmet storage compartments. Removing the rear seat bench cut weight by around 46 lb.

The center console structure of the new BMW M4 CSL is made entirely from CFRP. Carbon fiber interior trim and "CSL" badging below the headrests, center console, and on the rear panel is standard. The steering wheel is covered in Alcantara.

The price is $139,900.

Source: BMW

Published November 2022

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