Wild Rumor Claims Porsche Is Building New Flat Eight Powered SupercarAutoGuide.comMichael AccardiMon, September 21, 2026 at 3:37 PM UTCAdd us on Googlewild rumor claims porsche is building new flat eight powered supercarPorsche hasn't built a halo supercar since production of the plug-in hybrid 918 Spyder ended in 2015.Porsche explored concepts like the unproduced 919 Street and Mission X, but neither made it out of the factory. Now, reports from Germany suggest Porsche is preparing to re-enter the flagship segment with a standalone supercar known internally as the S1.This isn't the first time we've heard this rumor - at the start of September it was reported that Porsche was actively exploring a new mid-engine supercar to succeed the 918 Spyder, potentially based around the Audi Nuvolari. Earlier this year, new CEO Michael Lieters confirmed the company was actively working on a new supercar.AdvertisementAdvertisementNow, according to a report from Handelsblatt, the rumored S1 will sit above the 911 lineup with a price targeted around $574,000 USD.wild rumor claims porsche is building new flat eight powered supercarA Porsche Flat-Eight Engine Comeback?The most intriguing detail from the report is the alleged powertrain. Rather than relying strictly on a hybrid V8 or all-electric platform, the rumor indicates Porsche is eyeing a twin-turbocharged flat-eight engine, something the automaker has never done before.Porsche has experimented with an eight-cylinder boxer setup in the past-building a 5.0-liter, 750-horsepower prototype that revved to 9,000 rpm-but that project was shelved before reaching production. If Porsche does revive the flat-eight engine, it would be the brand's first production road car to use the layout.At this year's Goodwood Festival of Speed, RUF unveiled a 1,000 horsepower, twin-turbo flat-8 engine paired with a manual transmission. There were erroneous rumors earlier this summer that Porsche was interested in acquiring RUF to build small-batch supercars. While the report was denied by RUF, the two automakers do have an excellent relationship, and it does make you wonder if the two are working together on this project.AdvertisementAdvertisementPorsche could preview the S1 concept during its upcoming Capital Markets Day on October 7, 2026.Become an AutoGuide insider. Get the latest from the automotive world first by subscribing to our newsletterhere.