Group 4 (racing)

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Group 4 Lancia Stratos HF. The Stratos helped Lancia win the World Rally Championship in 1974, 1975 and 1976.

The Group 4 racing class, referred to a set of regulations for cars in sportscar racing and rallying regulated by the FIA. These regulations were introduced in the class structure changes for the 1966 motor racing season. The Group 4 class was replaced by Group B for the 1983 season.

1 Production requirements
2 Racing
3 Rallying
4 See also
5 Notes
6 References

[edit] Production requirements

Unlike sports-prototypes, for a car to be eligible in Group 4, the FIA required a minimum production run to be constructed over a 12 month period. The production requirement for Group 4, was 50 cars produced in 12 consecutive months, but this was latter reduced to 25 cars.

In Appendix J of the FIA International Sporting Code, there were groups defined for Touring cars, Grand Touring cars and Sports cars (numbers between brackets are required minimum production in 12 consecutive months).^[1]

Group 1: series-production touring cars (5,000)
Group 2: special touring cars (1,000)
Group 3: grand touring cars (500)
Group 4: sports cars (25)
Group 5: special touring cars
Group 6: prototype-sports cars

In the 1970s, the limited production sports cars were moved to the Group 5 (racing) class. Group 4 became the class for special grand touring cars with minimum production of 500 in 12 consecutive months.^[2]

Group 1: series-production touring cars (5,000)
Group 2: touring cars (1,000)
Group 3: series-production grand touring cars (1,000)
Group 4: special grand touring cars (500)
Group 5: sports cars (25)
Group 6: prototype-sports cars

In 1976, the Group 4 production requirement was reduced to 400 in 24 months.^[3]

[edit] Racing

In the World Endurance Championship, Group 4 cars originally played a supporting role to the prototypes. For example, in the 1966 season, while prototypes like the 7.0L Ford GT40 Mk II raced for outright victories, the 4.7L GT40 Mk I entries were competing for Group 4 class wins.^[4]

In 1968, the rules were changed, so that prototypes were limited to 3.0L, but Sports cars of up to 5.0L could be still be entered. It was also announced that the minimum production figure for the Group 4 sports cars, would be reduced to 25 cars. With larger engines than the prototypes, the Group 4 cars were now in contention for outright race wins. The Ford GT40 was the winner at Le Mans in both 1968 and 1969. Porsche began work on a production run of 25 cars for the Porsche 917 and Ferrari, with some financial help from Fiat, did the same with the Ferrari 512.^[5]

For the 1972 season, the emphasis was on the 3.0L sports prototypes, and the 5.0L Sports cars with limited production runs were no longer permitted. The Group 4 class was contested by production based grand touring cars such as the Ferrari 365 GTB/4 Daytona, Porsche 911 Carrera RS and the De Tomaso Pantera.

[edit] Rallying

The Group 4 regulations were also used as the basis for the World Rally Championships until they were replaced by the Group B regulations. In mid 1970s to early 1980s rallying, it was neccessary to produce 400 identical cars for homolgation as a Group 4 rally car. Notable cars included the Ford Escort RS1800, Fiat 131 Abarth, Lancia Stratos and the Audi Quattro.