Porsche’s Secret 991 Slantnose Project – What Is Going On?

A mysterious Porsche prototype has stirred excitement among enthusiasts. Recently spotted testing at the Nürburgring, the car looks like a 991-generation Porsche 911—but it is unlike anything that has rolled out of Zuffenhausen in years. This strange test mule features a bold “Flachbau” or slantnose design that instantly brings back memories of Porsche’s classic 935 racers. However, this is not a simple throwback; it could be a major hint at something new.

At first glance, the car wears the body and bumpers of a 991 GT2 RS, complete with the NACA-ducted hood and matching wheels. The rear section even features Manthey Racing covers, but that is where the familiarity ends. The front of the car has undergone a radical transformation, trading Porsche’s signature round headlights for a lower, flatter nose fitted with slim, Taycan-like lights hidden under camouflage stickers. It is a design choice that has Porsche fans buzzing with curiosity.

The massive rear wing adds more mystery. It rises from the center before flaring outward to connect with the wing’s edges, similar to—but not identical to—the track-only 911 GT3 R Rennsport that debuted in September 2023. The overall setup suggests aerodynamic experimentation or preparation for a potential new limited-production model.

The resemblance to the legendary 1980s “Flachbau” 911s is unmistakable. Between 1982 and 1989, Porsche produced 948 of those iconic flat-nose cars based on the 930 Turbo, each with a unique character and strong collector value today. Bringing that heritage into modern times could be Porsche’s latest move to blend nostalgia with innovation, much like it did with the 935, GT3 R Rennsport, and Sport Classic.

New information reveals that Porsche trademarked the names “Flachbau” and “Flachbau RS” last year, which suggests this project might be official. Whether this is a one-off creation, a special kit developed by Manthey Racing, or a test mule for upcoming limited-edition models like a GT3 Flachbau or GT3 RS Flachbau, it shows that Porsche is clearly experimenting with something special.

Whatever the purpose, this mysterious 991 proves that Porsche still loves to surprise its fans with unexpected ideas that bridge the gap between past and future. We’ll be watching closely for more details as testing continues.