Group 5 (racing)
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Group 5 is a FIA classification for cars in sportscar racing. Although began for sport car racers with a production run of 50, then 25; the category became revised in the mid '70s and would become a liberal silhouette formula category similar to production cars homologated in Groups 1 through 4, hence it became associated with large bodykits and horsepower output.
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[edit] 1st Generation Group 5 cars
In an effort to reduce the speeds generated at Le Mans and other fast circuits of the day by the 7 litre Ford prototypes, as well as to entice manufacturers who were already building 3 litre Formula One engines into endurance racing, the Commission Sportive Internationale (then the independent competition arm of the FIA) announced the World Championship of Makes would be run for 3 litre open prototypes for four years from 1968 through 1971.
Well-aware that few manufacturers were ready to immediately take up the challenge, the CSI allowed the participation of 5 litre sports car manufactured in quantities of 50 in the Sport category, which was known by the FIA as Group 5, targeting existing cars like the aging Ford GT40 and the newer Lola T70 coupe, hence the category became known by the FIA as Group 5 or commonly as the Sport 5000.
In April 1968, the CSI announced that the minimal production figure to compete in the Sport category of the World Championship of Makes (later the World Sportscar Championship) was reduced from 50 to 25 starting in 1969 through the planned end of the rules in 1971, mainly to allow the homologation of the Ferrari 275 LM and the Lola T70 (which was not manufactured in sufficient quantities, unless the open Can-Am T70s were counted as well) as there were still too few entries in the 3 litres Prototype category.
Starting in July 1968, Porsche made a surprising and very expensive effort to take advantage of this rule. As they were rebuilding race cars with new chassis every race or two anyway, they decided to conceive, design and build 25 versions of a whole new car for the Sport category with one underlying goal: to win its first overall victory in the 24 Hours of Le Mans. In only ten months the Porsche 917 was developed, based upon the Porsche 908, with remarkable technology: Porsche’s first 12-cylinder engine, and many components made of titanium, magnesium and exotic alloys that had been developed for lightweight hillclimb racers. Other ways of weight reduction were rather simple, like a gear lever knob made of Balsa wood.
When Porsche was first visited by the CSI inspectors only three cars were completed, while 18 were being assembled and seven additional sets of parts were present. Porsche argued that if they assembled the cars they would then have to take them apart again to prepare the cars for racing. The inspectors refused the homologation and asked to see 25 assembled and working cars.
On April 20 Ferdinand Piëch displayed 25 917s parked in front of the Porsche factory to the CSI inspectors. Piëch even offered the opportunity to drive one of the cars, which was declined.
During June 1969, Enzo Ferrari sold half of his stock to FIAT, and used some of that money to do what Porsche did 6 months earlier with the 917, to build 25 cars powered by a 5 litre V12 in order to compete against them. With the financial help of Fiat, that risky investment was made, and surplus cars were intended to be sold to racing customers to compete for the 1970 season. Within 9 months Ferrari manufactured 25 512S cars.
Ferrari entries only consisted of the factory cars, tuned by SpA SEFAC and there were the private cars of Scuderia Filipinetti, N.A.R.T., Écurie Francorchamps, Scuderia Picchio Rosso, Gelo Racing Team and Escuderia Montjuich which not receive the same support from the factory. They were considered as field fillers, never as candidate for a win. At Porsche, however, JWA Gulf, KG Salzburg who were then replaced by Martini Racing for the following season, received all direct factory support and the privateers like AAW Shell Racing and David Piper Racing received a much better support than Ferrari's clients.
The 917 instability problem was resolved with a revided rear hatch, which was called 917K (Kurzheck). There was a long tail version known as the 917LH (Langheck). Towards the end of the 1970 season, Ferrari entered some races with a new version of the 512, the 512M which had a revised bodywork.
During the 1970 season the FIA decided to eliminate the loop-hole Sport category at the end of the 1971 season, when the rules expired, so the big 917s and 512s would have to retire at the end of the year. Surprisingly, Ferrari decided to give up any official effort with the 512 in order to prepare for the 1972 season. 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 suffered popularity wise and would never 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, like it happened nineteen years before. The Gr.5 category, would temporally disappear until 1975, when it was reamended as a silhouette formula for production cars.
[edit] 2nd Generation Group 5 cars
For the 1972 season, the FIA made rule amendments to the category, they have now made redefined the rules for cars that are generally sold to the public, the rules restricted the width of the car, therefore production cars had narrower body width and were made up with wide body extensions. The rules however did not mention headlight heights, therefore when Porsche originally were to enter the 935 with the production headlight, they read the rules and discovered the loophole, therefore they raced the 935 with the trademarked flat nose. The category was also mostly associated with the wide boxy wheel arches and extravagant body style.
The category would be banished in 1982 in favour of the Group B regulation, but did continued to compete in JSPC, IMSA GTX category and other national sports car racing championships for a few more years.
The only non-circuit events that used Group 5 cars were in the Giro D'Italia Automobilistica rally. In Japan, the wide arch boxy with extended front spoiler body style is still favoured amongst bōsōzoku car drivers, impersonaters of the former and fans of the body style, who usually build a more over exaggerated body style.
[edit] Group 5 cars
[edit] 1st Generation
- Porsche 917 (includes the Kurzheck (K), Langheck (LH), widebody shortnose 917/20)
- Ferrari 512M/S
- Lola T70
- Ford GT40 Mk 1
[edit] 2nd Generation
- Porsche 935 (includes the 935-77, 935-78 known as the Moby Dick and the customer Kremer K3 and K4 and the JLP variation)
- BMW 320i
- Toyota Celica Turbo A22 (1st generation)
- Toyota Celica Turbo A45 (2nd generation)
- Nissan Skyline RS Silhouette Formula
- Nissan Nichira Impul Silvia ()
- Mazda RX-7 SA22
- Nissan Bluebird SSS Turbo
- BMW 3.0CSL
- BMW M1
- Ferrari 512BB
- Lancia Stratos Turbo
- Lancia Beta Montecarlo Turbo
- Ferrari 512BB LM
- Ford Capri
- Ford Escort
- Zakspeed Lotus Europa Gr.5
[edit] Racing Series/Category that used the formula (2nd Generation only)
- Deutsche Rennsport Meisterschaft
- IMSA GTX
- All Japan Sports Prototype Championship
- Formula Silhouette
