It’s been more than a decade since Porsche built a true flagship supercar. The 918 Spyder ended production in 2015, and despite some fascinating concepts and prototypes since then, none has stepped forward to take its place.
Porsche has certainly thought about it, though. The spectacular 919 Street was developed as a road-going interpretation of its Le Mans-winning prototype, only to stop at the clay-model stage.
Now another potential successor is taking shape, and this one could bring an engine configuration Porsche has never put into a production road car. A new report claims the company is developing a flagship with a flat-eight engine.
According to German business newspaper Handelsblatt, the project is internally known as “S1” and could become part of CEO Michael Leiters’ new strategy for Porsche. Investors may learn more when the company presents its “Sportwagenschmiede 2035” strategy on October 7.
A Flat-Eight Porsche Could Finally Happen

The biggest surprise is the rumored engine. Rather than another flat-six or an all-electric powertrain, the S1 is said to use an eight-cylinder boxer engine.
Porsche has plenty of history with flat-eight engines in racing, but it has never sold a production road car powered by one. The company has, however, experimented with the idea surprisingly recently.
Porsche previously built a Cayman-based prototype powered by a twin-turbocharged 5.0-liter flat-eight producing 750 horsepower and 738 lb-ft of torque. That engine revved to 9,000 rpm and was paired with a manual transmission, although the project never reached production.
It Won’t Be A Fancy 911
Handelsblatt’s reporting suggests the S1 would sit well above the 911 rather than simply becoming another variant of it. A starting price of around €500,000 would put it in an entirely different league than even Porsche’s most serious current road cars.
At this point, we have no idea what the S1 will look like, and its output, transmission, production numbers, and launch timing are also unknown factors. In fact, Porsche hasn’t even officially announced the car.
What Porsche has acknowledged previously is its interest in eventually putting something above the 911. Earlier this year, a company spokesperson even described the possibility to Motor1 using a particularly enticing word: “hypercar.”
Porsche Has Been Here Before

Porsche enthusiasts have good reason to be cautious. The 919 Street showed just how close the company could get to creating an extraordinary 918 successor before deciding against production.
The difference this time is Porsche’s changing strategy. Leiters has said the company needs to stay profitable while selling fewer vehicles, which makes expensive, highly exclusive models potentially valuable additions to the lineup.
October 7 could tell us whether the S1 is genuinely headed for production or destined to become another fascinating Porsche “what if.” If the flat-eight rumor proves accurate, though, waiting more than a decade for a 918 successor might finally pay off.
