On a recent episode of Jay Leno’s Garage, the renowned car enthusiast and former TV host turned his attention to one of BMW’s most elusive and impressive models: the 1994 BMW 850CSi. With only 1,519 built worldwide—and just 225 sold in the U.S.—this car has earned a reputation as the hidden gem of the E31 8 Series lineup. To help tell its story, Leno invited automotive journalist Jason Cammisa to provide deeper insights into the history and engineering behind this incredible machine. In case you haven’t figured it out, Cammisa is the proud owner of this beauty.
An M8 in Disguise
The 850CSi is more than just the top-spec version of the 8 Series—it’s the closest thing BMW ever built to an E31 M8. Even though, they did build a one-off that never went into production. While BMW chose not to officially badge it as an M car, this model was developed by BMW’s M Division, with extensive reengineering from top to bottom. At its core lies a reworked version of BMW’s V12 engine. Originally a 5.0-liter unit in the 850i, the engine was stroked to 5.6 liters, earning the new designation S70B56. This naturally aspirated masterpiece produces 375 horsepower and 406 lb-ft of torque, paired exclusively with a six-speed manual transmission—an unusual offering in the V12 luxury segment at the time.
Cammisa notes that the S70 engine wasn’t just more powerful; it was fundamentally different from the standard V12. BMW’s engineers made significant upgrades, including a revised crankshaft, higher compression pistons, and optimized intake and exhaust systems. The result? A car capable of 0-60 mph in six seconds and a top speed of 155 mph—electronically limited, of course.
A Grand Tourer Born for the Autobahn
When the E31 8 Series launched, it was a technological marvel. It was BMW’s first car designed entirely with computer-aided design (CAD), enabling engineers to create a body that was both stunning and aerodynamically efficient, with a drag coefficient of just 0.28. The 850CSi built on this foundation, adding performance and handling enhancements to transform the luxurious grand tourer into a capable sports car.
European models of the 850CSi came with four-wheel steering, further enhancing agility—a feature that would later trickle down to modern BMWs. The car also received aesthetic updates, such as wider wheels, redesigned bumpers for better aerodynamics, and four round exhaust tips that replaced the square units on lesser 8 Series models. BMW Motorsport-branded door handles and subtle trim upgrades underscored the car’s performance pedigree.
In its day, the 850CSi was a niche offering, overshadowed by BMW’s other models and saddled with a hefty price tag. But time has been kind to this rare machine. Today, it’s celebrated as a showcase of BMW’s engineering brilliance during the 1990s and a symbol of the M Division’s ability to push boundaries. The S70 engine even went on to inspire the V12 used in the McLaren F1, adding another layer of mystique to the 850CSi’s story.
Let’s take a look!
