Regular readers of this site will be well familiar with the Porsche 911 GT1 endurance race cars of the mid-1990s and their street-legal homologation special known as the Straßenversion, German for “street version.”

Just 20 of the homologation specials were sold directly to the public, all of them built in 1997 and featuring the front-end styling of the 911 on sale at the time, the 996 generation. However, there were four additional prototype examples built, and one of these turned up to the 2021 Concorso d'Eleganza Villa d'Este held in Italy earlier this month. Fortunately Automotive Mike was there to bring us this video.

This particular 911 GT1 Straßenversion is one of only two prototypes built in 1996. One of those prototypes was retained by Porsche while the other, featured here, was sold at one point to Bahraini car collector Khalid Abdul Rahim.

These early prototype 911 GT1 Straßenversions were based on the 1996 911 GT1 race car, featuring the same 3.2-liter twin-turbocharged flat-6 mounted in a mid-engine position (as opposed to the regular 911's rear-engine positioning). The prototypes had a peak output rated at 544 hp versus the race car which had closer to 600 hp, and they also skipped the race car's carbon-ceramic brake rotors in favor of regular steel units. The suspension was also not as extreme as in the race car, but as the video shows, driving one on the street is still pretty much impossible.

While the two early prototypes were mechanically similar to the 20 customer cars that came later, there were some differences, the main one being the styling that resembled the earlier 993-generation 911. The customer cars were also based on the 911 GT1 Evo race car built for the 1997 motorsport season, and not the original 1996 911 GT1 race car that the two prototypes were based on.

There was also one prototype built in 1997 that matched the specification and design of the customer cars built that same year, plus a one-off 911 GT1 Straßenversion homologation special built in 1998 for an updated version of the 911 GT1 race car developed for the 1998 motorsport season. These two additional 911 GT1 Straßenversions have been retained by Porsche.