According to Wikipedia "The Shelby Mustang is a high performance variant of the Ford Mustang. The 1965, 1966 and 1967 Shelby's were known as "Shelby Cobras" and were a series of Ford Mustangs which were specially modified by Carroll Shelby's company and sold as a series. The program was factory-sponsored by Ford to compete with the Corvette, also factory-sponsored by Chevrolet, neither of which could be built for the sales price charged. In 2007, following the introduction of the Fifth-generation Ford Mustang the Shelby nameplate was revived for new high performance models"