In the world of rare sports cars, few are as elusive—or as historically significant—as the Porsche 645. Built in the mid-1950s as an experimental successor to the 550 Spyder, the one-off prototype was destroyed in a fiery crash in 1956. Nearly seven decades later, the car has returned to life through an extraordinary modern recreation crafted by Hardt Classics, an Australian Porsche specialist.
The Porsche Type 645, often nicknamed “Mickey Mouse” for its compact proportions and twitchy handling, represented a critical developmental step between the 550 Spyder and the later 718 RSK. Conceived under the direction of engineer Egon Forstner with input from Ernst Fuhrmann and Heinrich Klie, the car introduced innovations in weight reduction, aerodynamics, and chassis design.
Built with a magnesium body and a shortened wheelbase, the original prototype weighed just 550 kilograms and was powered by Porsche’s 1.5-liter, four-cam Type 547 engine. This complex flat-four produced around 135 horsepower—impressive for its time—and was paired with a four-speed manual gearbox. The car’s spaceframe construction and integrated oil-cooling system were experimental touches that later influenced Porsche’s endurance racing efforts.
Unfortunately, the 645’s racing life was brief. After a fourth-place finish at Solitude in 1956, driver Richard von Frankenberg crashed the car at the AVUS race later that year. The prototype was completely destroyed, leaving only factory drawings, photographs, and written records.
Hardt Classics has now resurrected the 645 using those same original blueprints. The recreation features a tubular steel spaceframe, hand-formed aluminum bodywork, 356 Carrera GT drum brakes, and period-correct components throughout. Although it currently lacks the rare four-cam engine, the project captures the spirit and precision of Porsche’s 1950s racing craftsmanship.
Offered for sale in Victoria, Australia, this faithful recreation stands as both a tribute and a time capsule—restoring a lost chapter of Porsche’s motorsport evolution that helped pave the way for legends like the 550A and 718 RSK.