• Looking Back at the E31 BMW M8 Prototype

Probably the most epic M car BMW never made

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BMW is a name mostly associated with pure driving pleasure - in fact, it was even their slogan at one point. Even though they are making some pretty controversial cars, in the eyes of the fans, there’s no denying the fact, they’ve made some epic cars, over the years. One of the most epic BMW cars, however, was one that was never sold – the BMW M8 E31. Despite BMW’s decision not to put the M8 E31 into production, there are a lot of interesting facts surrounding it.

It has something in common with the Golf GTI

In terms of the level of technology and engineering involved, the cars are in two completely different galaxies. That said, they have a lot in common in terms of their inception. Just like with the Golf GTI, a group of talented specialists decided to make a performance version of the base car and impress BMW, with what they think a high-performance gran-tourer should be. Among the dedicated team were Gerhard Richter – a chassis specialist, Karl Heinz Kalbfell – then BMW chairman of motorsport, and Paul Rosche – a genius engine designer, responsible for the M70 V-12 used in the McLaren F1. He also designed the most powerful Formula 1 engine, ever. Most of these names had prior involvement with BMW and are partly responsible for some of the most iconic models of the brand.

Only one prototype was built

Looking Back at the E31 BMW M8 Prototype
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Unlike the Golf GTI, the BMW M8 E31 was not deemed feasible by BMW management, despite the dedicated team. Nevertheless, one car was finished.

The car was recently restored and is fully functional. According to the latest updates, the one-off M8 E31 is currently located at the BMW M GMBH studio, where it’s proudly displayed among other highlights of BMW’s M division.

It was meant to be a Ferrari-killer

1992 - 1997 Ferrari 456 GT
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During the late 1980s and early 1990s, Ferrari was on a roll. When the small team started working on the BMW M8, they envisioned a V-12 super-gran-tourer that would take on the latest and greatest from the Prancing Horse. During the early 1990s, Ferrari had the 456, which was also a 2+2 V-12 GT car. That one has a 5.5-liter naturally-aspirated V-12, producing 442 horsepower (325 kW) and 406 pound-feet (550 Nm), which was enough for a 5.0-second sprint to 62 mph (100 km/h), on its way to 186 mph (300 km/h).

Ferrari 456 specifications
Engine 5.5-liter naturally-aspirated V-12
Horsepower 442 HP
Torque 406 LB-FT
0 to 62 mph 5.0 seconds
Top Speed 186 mph

It was going to be the fastest 1990s gran-tourer

Looking Back at the E31 BMW M8 Prototype
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The dedicated team, indeed, went all-out when developing the Ferrari-slayer. Although initially the top speed was calculated at 198 mph (319 km/h), it was said that the BMW M8 E31 could easily break the 200 mph (322 km/h) mark. The 0 to 62 mph (100 km/h) time was calculated at around 4.2 seconds. That’s also with the mediocre tire technology of the 1990s.

Not a McLaren F1 engine

Looking Back at the E31 BMW M8 Prototype
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When the team was working on the engine, they took the normal S70 5.0-liter V-12 unit from the 850i and did extensive modifications to it. Initially making 296 horsepower (221 kW) and 332 pound-feet (450 Nm), the lazy unit was quite mediocre even for the time. The same engine was used for the basis of what would become the M70, which was used in the McLaren F1. However, the engine that powered the M8 is not a direct descendant of the unit found in the F1, even though it shares the exact same 6,064 cc (370 cui) capacity. Rather, it is a different interpretation of the original S70 5.0 V-12. According to different sources, the BMW M8 E31 produced between 550 and 640 horsepower (410 – 477 kW) and up to 479 pound-feet (650 Nm). Power was sent to the rear through a six-speed manual. Although only one E31 M8 exists, three of these engines were made.

E31 BMW M8 Prototype specifications
Engine S70 5.0-liter V-12
Horsepower 550 - 640 HP
Torque 479 LB-FT
Transmission six-speed manual
0 to 62 mph 4.2 seconds
Top Speed 200 mph

It was much lighter than the base 850i

1989 - 1999 BMW 8-series
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1990bmw8series

The BMW E31 has always been a gran-tourer first and a sports car second. You can tell that the base version of the German coupe was not built with lightness in mind. The BMW 850i has a dry weight of 3,946 to 4,134 pounds (1,790 – 1,875 kg), depending on what gearbox and optional extras it had. The M8, had they put it into production, would have had to compete with cars like the Ferrari 456 or the 550 Maranello, so it needed to be nimbler.

The E31 M8 managed to shave nearly 990 pounds (450 kg).

The 3,196-pound (1,450 kg) figure was achieved through the extensive use of glass-reinforced plastic for the exterior panels, as well as a stripped interior, now featuring racing bucket seats and harnesses and rear-seat delete. It also had Lexan windows, where only a small section would open, just like in a racecar.

It’s very aerodynamic

Looking Back at the E31 BMW M8 Prototype
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Although the E31 M8 was never produced, it certainly had a lot to boast about. Among the achievements of the German performance coupe is its incredibly low drag coefficient. When initially designing the BMW E31, the goal was for it to have a drag coefficient of less than 0.3. The end result was a figure of 0.29. For comparison, a later Lamborghini Countach has a drag coefficient of 0.42 and a Ferrari Testarossa – 0.36. Automotive designer Klaus Kapitza’s input had a key role in optimizing the Bavarian coupe’s aerodynamic efficiency.

It was too expensive to put in production

Looking Back at the E31 BMW M8 Prototype
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When the dedicated team approached BMW management, the numbers were run. In the end, they estimated that, in order for the E31 M8 to be feasible, it has to be twice as expensive as the top-of-the-line Porsche 911 – a car with an already established status, as one of the best sports cars of all time. Back in those days, the 911 (964 Turbo S variant cost roughly $90,000. In today’s money, that equates to just over $181,000. Essentially, the BMW E31 M8 would have cost around $180,000 or $362,000, in today’s money. Because of this, the M8 E31 remained a one-off special.

Dim Angelov
Dim Angelov
Born in 1992, I come from a family of motoring enthusiasts. My passion for cars was awoken at the age of six, when I saw a Lamborghini Diablo SV in a magazine. After high school I earned a master’s degree in marketing and a Master of Arts in Media and Communications. Over the years, I’ve practiced and become skilled in precision driving and to date have test driven more than 250 cars across the globe. Over the years, I’ve picked up basic mechanical knowledge and have even taken part in the restoration of a 1964 Jaguar E-Type and an Alfa Romeo Giulia Sprint. Lately, I’ve taken a fancy to automotive photography, and while modern cars are my primary passion, I also have a love for Asian Martial Arts, swimming, war history, craft beer, historical weapons, and car restoration. In time, I plan my own classic car restoration and hope to earn my racing certificate, after which I expect to establish my own racing team.  Read full bio
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