The FIA introduced new motor sport regulations for the 1966 World Sportscar Championship that saw homologation for Group 3 Grand Touring cars increased from 100 to 500 cars. Further up the chain was the Group 4 category for Sports cars (with a 50 car production requirement) and Group 6 for Prototypes (which had no minimum production requirement).

In anticipation of the new rules, Ferrari created the 330 P3 Group 6 Prototype, the Dino 206 S for the Group 4 Sports class and the 275 GTB/C for Group 3 GT racing.

Despite its almost identical appearance to the homologated 275 GTB base car, the 275 GTB/C (of which just twelve were built) featured an array of significant upgrades to include a stiffer, lighter Tipo 509A chassis, uprated suspension, a long-range fuel tank, a trick Tipo 213/Comp engine riddled with magnesium alloy parts, a close-ratio five-speed gearbox (housed in a mgensium casing), dramatically lightened bodywork and a pared-back interior.