Reyn Speed Shop 858 CSL: V10-Powered BMW 8 Series Reinvention

Welcome to the Reyn Speed Shop’s 858 CSL, a name that perfectly reflects the car's transformation. Unlike some modern BMW badges, this one is true to its roots. The "858" signifies the 5.8-liter engine beneath its newly sculpted hood, while "CSL" pays homage to the lightweight, high-performance spirit that defines BMW’s legendary Coupe Sport Leichtbau models.

The Heart of the Beast: A 5.8-Liter V10 Engine

The transformation starts with the engine. Out went the original V12, and in its place is a heavily modified version of the 5.0-liter V10 from the E60 BMW M5. Why opt for a screaming V10? According to Rey Rivera, Reyn Speed Shop's founder, it was about maintaining an exotic and technically advanced drivetrain. “The E60 S85 was the ticket for us,” Rivera told TopGear.com.

To bring this vision to life, Rivera partnered with Carbahn—Steve Dinan’s renowned tuning company—to expand the V10 to a 5.8-liter 'street' spec. While the 858 CSL hasn’t hit the dyno yet, Rivera estimates it will deliver at least 630 horsepower and 489 lb-ft of torque, far surpassing the performance of the original 850i’s V12.

A Manual Gearbox for a Pure Driving Experience

This power is channeled through a six-speed manual gearbox, a rare feature even for the E60 M5. This setup promises an engaging driving experience, although it might leave your arms a bit tired after taming all that power. While performance figures remain untested, it’s safe to assume that the 858 CSL will be blisteringly fast.

A Symphony of Sound and Performance

The roar of the V10 is unmatched, with Rivera praising its unique sound and flexible power band. To manage this power, the car retains the stock Electronic Damper Control (EDC) shocks and struts from the original 8 Series. However, Reyn Speed Shop is collaborating with Moton to develop a custom four-way suspension system, fine-tuned to handle the car’s new lightweight profile.

Lightweight Transformation: Shedding Pounds and Adding Style

One of the most impressive aspects of the 858 CSL is its weight—or lack thereof. Rivera, working alongside designer Jon Sibal, managed to strip 313 kg (689 lbs) from the car’s bulk, bringing its total weight down to around 1,500 kg. This significant weight loss is thanks to the extensive use of carbon fiber body panels, which also contribute to the car’s aggressive new look.

Sibal and Rivera took inspiration from classic BMW M designs, incorporating flared arches reminiscent of the E30 M3, the front valance of the E39 M5, an integrated rear spoiler that nods to the E46 M3 CSL, and even the Vader seats from an E36 M3. These elements combine to create a car that feels both familiar and unique.

Modern Tech Meets Classic Design

While the 858 CSL’s exterior has been radically altered, the interior remains true to the original E31 8 Series design. However, it has been updated with select E60 M5 controls to enhance functionality and ensure seamless integration of the modern drivetrain. This blend of old and new ensures that maintaining and sourcing parts for the 858 CSL will be straightforward, thanks to the compatibility with the E60 M5.

A Four-Year Labor of Love

The 858 CSL is the result of four years of dedicated work. Rivera chose the E31 8 Series as the foundation for this project because of its potential to integrate modern technology and performance while retaining its classic appeal. By blending the E31 chassis with E60 components, Reyn Speed Shop has created a restomod that not only looks stunning but also offers OEM-level diagnostics, serviceability, and parts availability.

Conclusion: A Masterpiece of Engineering and Design

The Reyn Speed Shop 858 CSL is a remarkable fusion of classic BMW design and cutting-edge performance. With its V10 engine, lightweight construction, and carefully crafted aesthetic, it stands as a testament to what can be achieved when passion, creativity, and technical expertise come together. This is not just a car; it’s a rolling piece of art that redefines what a BMW 8 Series can be.