Porsche Developed Flat-Eight, Manual Hypercar, But Canceled It The Last Moment

This monster mill was supposed to be fitted to a Carrera GT/918 Spyder replacement.

Porsche's legendary brand almost launched a sports car equipped with a 5.0-liter twin-turbocharged flat-eight engine, a rare deviation from their typical six-cylinder engine selection. Astonishingly this Engine was connected to the same project that led to the creation of the 4 cylinder 718 Cayman.

The veil of secrecy surrounding this enigmatic flat-eight engine was lifted when Porsche's global e-fuel specialist, Marcos Marques, divulged some information to The Intercooler. While Porsche's commitment to e-fuels is a beacon of hope during a time when gasoline engines are facing bans, the focus is now on the flat-eight engine's 750 horsepower.

When Marques was asked about the origins of the four-cylinder Cayman, he revealed that it was "originally part of a bigger project, one that involved another car that would have made a lot more sense of the flat-four project." This monster mill was intended to be installed in a potential replacement for the Carrera GT/918 Spyder.

Marques revealed more information about the engine design he had previously mentioned, stating that there was another car with a bigger version of the engine. This engine had eight cylinders instead of four, two turbos, and was used in a Cayman chassis. It produced 750 horsepower 1000 Nm (738 lb-ft) of torque and had a red line of 9000 rpm. According to Marques the car was quite crazy and sounded amazing. He also mentioned that the engine in a Cayman chassis with a manual gearbox was quite wild.

The current top model in the Cayman range, the Cayman GT4 RS, produces 493 horsepower and can reach 60 mph in 3.2 seconds. It is hard to imagine what a 750hp eight-cylinder engine would do in the same vehicle.

The 5.0 liter Twin Turbo 8 cylinder engine was initially planned to be used in a new mid Engined sports car that would have replaced both the carrera GT and the 918 spyder. A prototype of this car was tested on roads near Weissach for over a year, but it was never given a name. However the decision makers at Porsche ultimately decided that the timing was not right for this particular Sports car and it was canceled.

There were also Rumors in 2016 about a new Porsche Sports car called the 960 which would have featured a flat eight quad turbo engine and competed with the likes of the Ferrari 488. Unfortunately this car also never made it to production.

Marques, who was involved in various engine projects, revealed that a quad-turbo version of the 991-gen 911 was considered but ultimately deemed too challenging to package in the rear of the car. The technology for this engine had already been developed prior to the Bugatti Veyron's release, which ended up using the sequential four turbo technology.

Marques also mentioned two other Engine projects that never made it to production a 2nd gen Audi R8 with a 4 cylinder engine and a V10 powered Volkswagen Golf 5. With Porsche's increasing focus on electrification, the possibility of an eight-cylinder Cayman or other sports car may have passed. However there are still enthusiasts who would try to fit a big V8 Engine into a small Car like the Cayman.