FIA Group 5

Group 5 was an FIA motor racing classification which was applied to four distinct categories during the years 1966 to 1982. Initially Group 5 regulations defined a Special Touring Car category and from 1970 to 1971 the classification was applied to limited production Sports Cars restricted to 5 litre engine capacity. The Group 5 Sports Car category was redefined in 1972 to exclude the minimum production requirement and limit engine capacity to 3 litres. From 1976 to 1982 Group 5 was for Special Production Cars, a liberal silhouette formula based on homologated production vehicles.

In 1966 the FIA introduced a number of new racing categories including one for highly modified touring cars, officially known as Group 5 Special Touring Cars. The regulations permitted vehicle modifications beyond those allowed in the concurrent Group 1 and Group 2 Touring Car categories. Group 5 regulations were adopted for the British Saloon Car Championship from 1966 and for the European Touring Car Championship from 1968. The Special Touring Cars category was discontinued after the 1969 season.

For the 1970 season, the FIA applied the Group 5 classification to the Sports Car class which had previously been known as Group 4 Sports Cars. The minimum production requirement remained at 25 and the engine capacity maximum at 5 litres as had applied in the superseded Group 4. Group 5 Sports Cars contested the FIA's International Championship for Makes in 1970 & 1971, alongside the 3 litre Group 6 Prototype Sports Cars.

During 1970 the FIA decided to replace the existing Group 5 Sports Car category when the rules expired at the end of the 1971 season, so the big 917s and 512s would have to be retired at the end of that year. Surprisingly, Ferrari decided to give up any official effort with the 512 in order to prepare for the new 1972 season regulations. But many 512s were still raced by private teams, most of them converted to M specification. As a result of the rule change, sports car racing popularity suffered and did not recover until the following decade, with the advent of Group C which incidentally were forced out of competition in favour of the 3.5 atmo engine formula, reminiscent of events nineteen years previous.

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