Concept model of the Porsche 911 Turbo presented at the 1973 Frankfurt Motor Show

It was at the 1973 Frankfurt Motor Show that Porsche first publicly announced that it was developing a new high-powered 911. It was to be powered by a turbocharged flat-six. It would eventually become the 930-generation 911 Turbo.

This announcement was accompanied by the unveiling of the concept car after it had been restored by its current owner to restore it to the condition in which it debuted at Frankfurt.

The car Porsche unveiled several years ago did not actually feature a turbocharged engine. Due to development delays, Porsche fitted a simulated wooden turbocharger to a naturally aspirated engine and painted it to look like metal. This car was the first 911 to bear the word "turbo," in this case with hand-painted graphics on the sides.

It was based on a 1973 911 S with chassis number 9113300157, but was given the late production 911 Turbo's wide body, huge rear wing, and large diameter Hooks-style wheels.

The concept was subsequently presented at several additional shows and was eventually used as a development mule for race car parts after production of the 911 Turbo began in 1974. in 1975, racing driver and Porsche's Australian import agent, Alan Hamilton discovered the car during a visit to the Porsche factory and negotiated its purchase.

The car has since been bought and sold several times and is currently in Europe, where it will be unveiled at an event at Hampton Court Palace in England beginning August 30.

It is not considered the first 911 Turbo. That honor goes to another narrow-bodied car with a 2.7-liter turbocharged flat-six and no "turbo" markings whatsoever, delivered on the 70th birthday of Louise Piech, daughter of Porsche founder Ferdinand Porsche. That was also in 1973, albeit before the Frankfurt Motor Show that year. The car is now on display at the Porsche Museum in Stuttgart.