Group 3 GT cars

The Group 3 racing class referred to a set of regulations for Grand Touring Cars competing in sportscar racing and rallying events regulated by the FIA. These regulations were active, in various forms, from 1957 to 1981

Regulations for Grand Touring Car racing were first defined when the FIA issued "Appendix J" for Touring Cars and GT Cars in 1954. The term Group 3 was in use by 1957 and by 1960 a minimum production of 100 units in 12 consecutive months was required to allow homologation into Group 3. An FIA GT Cup was instituted in 1960 and the GT category was featuring prominently in most rounds of the World Sports Car Championship. For 1962 the FIA replaced the World Sports Car Championship with an International Championship for GT Manufacturers, the new title being awarded each year through to 1965.

The FIA introduced a new Group 3 Grand Touring Car category in 1966 as part of a major revision of the Appendix J regulations. The production minimum required for Group 3 homologation was raised to 500 units and models such as the Ferrari 250 GTO and Porsche 904 were reclassified to the new Group 4 Sports Car category with its lower 50 unit minimum. The International Championship for GT Manufacturers was discontinued for 1966 and replaced by the International Championship for Sports Cars. GT cars were eligible to compete with the Group 4 cars in rounds of the International Championship for Sports Cars in 1966 and 1967 and then in the new International Championship for Makes with Group 4 Sports Cars and Group 6 Prototype-Sports Cars in 1968 and 1969. An International Cup for GT Cars was contested concurrently with the Makes Championship from 1968.

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