Only 2 Of These Flat-8-Powered Porsche Sports Cars Were Ever Built
When thinking of eight-cylinder engines, V8s are usually the first thing that comes to mind. If you have a particular interest in pre-war cars, you might think of the straight-eight. One layout that doesn’t get mentioned very often, however, is the flat-eight. This rare beast was occasionally spotted in aircraft and racing cars, but when it comes to road cars, automakers kept their distance from it. The closest the car world ever got to a flat-eight-powered model was a one-of-a-kind (well, two-of-a-kind) prototype built by Porsche in the late 1960s: the 914/8, based on the 914.
The 914 was the source of inspiration for several other cars, from race cars to prototypes, but the 914/8 was one of the most innovative variations spawned from Porsche's mid-engined sports car. Never intended to become a production model, it was simply a way for Porsche to test the limits of its engineering and design capabilities, using a race car engine in a road car body in much the same way the Mercedes-AMG One has done today.

1969-1972 Porsche 914 Orange Front Angled View
But why did Porsche stick a flat-eight into this roadgoing sports car? And what drove the automaker to build a second one?

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Porsche
Porsche is a German sports car manufacturer and part of the broader Volkswagen Group since August 2012. Founded in 1931 by Ferdinand Porsche, the brand is most famous for the 911 line of sports cars, which first launched in September 1963. But it was the Porsche 356 that came first, and subsequently, Porsche has expanded its model lineup to include a variety of sports cars, supercars, SUVs, sedans, and even EVs. Porsche has a rich history in motorsport, with 19 outright Le Mans victories to its name, among various other titles.
The Porsche 914/8's Unique History

Porsche
The name Porsche 914/8 might not be immediately familiar, even to Porsche enthusiasts: that is because the 914/8 is an extremely rare prototype, based on what is already an often-forgotten sports car, the 914. Shortly after the launch of the 914 in 1969, Porsche decided to experiment with its design and mechanical components, creating something slightly different. Instead of the Volkswagen flat-four engine found in the standard 914 of the time, Porsche opted for another unusual layout: a flat-eight engine, more specifically the one already found in the 908 race car.
The Porsche 914/8 In Numbers | |
---|---|
Engine | 3.0-liter flat-eight |
Horsepower | 300 hp (Car 1) / 260 hp (Car 2) |
Year Built | 1969 |
Two 914/8 cars were built. The first (pictured above) was not road-legal and was created as an engineering exercise at the behest of one Ferdinand Piëch; yes, that Ferdinand Piëch, the man behind the VW Group's creation of cars such as the Bugatti Veyron, Volkswagen Phaeton, and the ultra-efficient XL1. This car was finished in orange and had a power output of approximately 300 horsepower, according to Porsche, although some sources claim as much as 350. Piëch, then head of development for Porsche, drove the car as a test vehicle, despite it not being officially road-legal.

Porsche 914-8 car number 2 owned by Ferry Porsche
The second car was road-legal but differed from the first in a few ways. While it retained the 3.0-liter boxer engine, it swapped the fuel injection of the first prototype for carburetors, reducing power to approximately 260 hp. Finished in silver, this road-registered car was gifted to Ferry Porsche, Piëch's uncle and the son of Porsche's founder, for his 60th birthday.
While these cars are now known as the 914/8, following the naming convention used by other 4- and 6-cylinder derivatives to denote the engine in each model, they were known at the time as the 914 S. While no further models were equipped with eight-cylinder engines, these two inspired a series of high-performance 914 derivatives, including the 6-cylinder 914/6 GT in 1971.

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A Brief History Of The Porsche 914

1970 Porsche 914 Yellow Front Angled View
Before there was the Porsche 914/8, there was the 914: a two-seater, mid-engined roadster with a targa-top roof made from fiberglass-reinforced plastic. The 914 was the result of a collaboration between Porsche and Volkswagen, who wanted to create a replacement for the 912 and the Type 34 Karmann Ghia respectively. During the development of the 914, Porsche handled the car’s design, while Volkswagen took care of the powertrain, supplying the Type 4 engine that also powered the VW model of the same name. The 914 was the first model to be marketed by the new joint company founded by the two marques: the VW-Porsche Vertriebsgesellschaft (VG). Ferdinand Piëch, who was in charge of research and development at Porsche at the time, supervised the design and release of the 914, which remained in production from 1969 to 1976.
Volkswagen and Porsche initially disagreed on how the new car would be badged: the flat-four-powered version was originally due to be branded as a Volkswagen, while the variant known as the 914/6 (powered by a Porsche flat-six engine) was going to be branded as a Porsche. Porsche, meanwhile, had uncertainties about both models being sold in the US simultaneously. Eventually, a compromise was reached: in the US, the 914 was sold as a Porsche, while in Europe it was badged as a “Volkswagen-Porsche”.
The 914 underwent a few updates during its short production run; the 1.7-liter flat-four was replaced by a 1.8-liter version, while the 914/6 was discontinued and replaced by another flat-four variant powered by a 2.0-liter unit. A few changes to the bodywork, such as the addition of new bumpers and updated headlight surrounds, were also made throughout the model’s lifespan.
When the 914 was eventually discontinued after just seven years of production, its 2.0-liter engine went on to power the 912E, a stop-gap model (and another Porsche-VW joint development) that stayed on the market for just a year before the introduction of the 924.

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Other One-Off Variants Of The 914

1970 Porsche 914/6 Murene by Heuliez Orange Front Angled View
The 914/8 was only one of several unique concepts and prototypes based on the 914 to emerge over the years. In 1970, Porsche built a Group 4 (Grand Touring) homologation car dubbed the 914/6 GT (or the 914/6 R in the United States). It was based on the flat-six-powered version of the 914 (the 914/6), hence the name.
The 914 was also used as a starting point for projects by designers not affiliated with Porsche. In the early 70s, French designer Jacques Cooper was working for Brissonneau and Lotz, a builder of locomotives and railway wagons. However, when he created a unique concept car based on the 914, coachbuilder Heuliez took an interest in the project. The result was a one-off prototype called the Heuliez Murene, which earned a spot at the Paris Auto Show but never became a production model.

1971 Porsche 916 Prototype
Another car based on the 914 which never saw a full production run was the 916: in 1971, Porsche used the 914 as a base to create an innovative prototype that modified many of its features. The 916 was quite different, both stylistically and mechanically, from the original car; its wider wheels and new fenders gave it a more aggressive appearance. On the performance front, the transmission was upgraded, and ventilated disc brakes were added to all four wheels. A total of eleven 916s were built, only one of which was a US-spec car.
The 914's Legacy Of Mid-Engined Sports Cars

Porsche 914 And Porsche Cayman (1)
Porsche is arguably most famous for putting the engine in the wrong place, with the 356 and 911 featuring a rear-mounted engine, despite it arguably being less than ideal. But the 914 introduced the brand to mid-engine cars - at least from the perspective of production vehicles. Before this Porsche had built mid-engine racers, but never roadgoing machinery in that configuration. However, subsequently, mid-engined Porsches have made a comeback.
It took 20 years after the 914 for the configuration to return, but when it did, it was in one of the most important models to ever bear the Porsche crest: the Boxster. The Carrera GT and 918 Spyder utilized mid-mounted engines, too, but the mainstream torch of the layout has been carried by the Boxster, and later the Cayman. Today, models like the 718 Cayman GT4 RS and 718 Spyder RS are some of the finest driving Porsche sports cars of all time, but it can be argued neither would've existed if not for the 914.

Porsche 914 and Cayman GT4