The past 50 years has been fruitful for BMW M. Among M creations, the CSL – which stands for Competition, Sports and Lightweight – launched the sub-brand into the higher realm of performance.

Examples of these are the 1973 BMW 3.0 CSL, 2003 BMW M3 CSL and the new BMW M4 CSL.

Nevertheless, many CSL models remained as secret prototypes, and BMW M just revealed four of them in a short video.

BMW M3 CSL Prototype E46 V8: A Car We Want To Drive

The M3 CSL V8 features a high-rev 4.0-liter engine that BMW M independently developed, offering 430 hp of output.

Its S65VB40 engine was a pre-trial carrier based on the S62 8-cylinder employed in other BMW models.

While the M3 CSL V8 remained a one-off, the insights gained in its development flowed into the M family of engines, such as the S85 V10 and S65 V8.

The S65B40 engine went into production for the BMW M3 (E90) with 420 hp.

RELATED: BMW Unveils The 2023 M4 CSL Limited Edition

BMW M5 CSL Prototype E60 V10 Has Awesome Engine

BMW M5 CSL V10 secret garage prototype, front quarter view driving
Via: BMW M

To mark its 25th anniversary, BMW M built this prototype from the M5 series as a lighter M5 CSL (by 330 lbs) featuring a carbon fiber roof, Recaro seats, rear seat delete, and forged 18-inch wheels.

BMW replaced the series sequential manual gearbox (SMG) with a double-clutch transmission (DCT).

It features a revised high-rev 5.5-liter V10 engine providing around 630 hp.

Boasting a fine-tuned suspension, the jubilee M5 CSL managed to complete a lap at the famed Nürburgring circuit in just 7 minutes and 50 seconds.

This BMW M6 CSL Prototype E63 V10 Is All Kinds Of Awesome

BMW M6 CSL secret garage prototype, dark red, front quarter view, in hangar
Via: BMW M

The main focus of the BMW M6 CSL prototype was aerodynamics.

While the car is as light as possible by employing lightweight door panels and central console, its developers centered their attention on achieving clever airflow.

The prototype featured active aerodynamics, in the form of an automatic tail spoiler and a retractable front spoiler, it also features double-strut M exterior mirrors.

RELATED: After Sitting In A Garage For Decades, This BMW 3.0 CSL Turns Electric

BMW M2 CSL Prototype F87: A Car With A Racing Heart

BMW M2 CSL secret garage prototype, blue, front quarter view in hangar
Via: BMW M

BMW M intended the M2 CSL Prototyp as a car that improves on the speedy nature of the 2018 BMW M2 Competition, so, BMW M engineers brought in an M2 Competition and borrowed certain elements from the M4 GTS. While the BMW M2 Competition offered 410 hp of output and 405 lb-ft of torque, the M2 CSL Prototyp came with 450 hp and 405 lb-ft of torque.

This two-seater features bucket seats, rollover bar, CFRP central console, carbon rear wing and carbon ceramic brakes.

BMW M built the M2 CS at the same time, but with a cabin more suitable for daily use.

Source: BMW M