Three years after Porsche launched the 997-generation 911 GT2—already the fastest street-legal 911 ever built—the limited-production GT2 RS arrived and stole the accolade.

The standard GT2 added 50 horsepower more than the 997-era Turbo, and the GT2 RS upped that even further to 620 horsepower, in part by increasing boost on the twin-scroll turbochargers.

The GT2 RS was put on a strict diet, resulting in an overall weight saving of 68 kilograms over its GT2 stablemate, achieved through the use of a single mass flywheel, a carbon fibre bonnet, various steel parts replaced with aluminium equivalents, lightweight centre-lock wheels, and even lighter carpets.

This Italian-delivered, one-owner example GT2 RS was built to 2011 model year specification and finished in Carrara White over a Black leather and Alcantara-trimmed interior with Guards Red seatbelts.

The Porsche was attractively configured with the exterior carbon fibre package, Porsche Ceramic Composite Brakes (PCCB), Black inst...