Group B was a set of regulations for grand touring (GT) cars used in sports car racing and rallying introduced in 1982 by the Fédération Internationale de l'Automobile (FIA). Although permitted to enter a GT class of the World Sportscar Championship alongside the faster and more popular Group C prototypes, Group B cars are commonly associated with international rallying during 1982 to 1986, when they were the highest class used in the World Rally Championship (WRC) and regional and national rally championships.
The Group B regulations fostered some of the fastest, most powerful, and most sophisticated rally cars ever built, and their era is commonly referred to as the golden era of rallying.Top Gear website: The corner that killed Group B However, a series of major and fatal accidents occurred amid ongoing concerns over unchecked evolution of the cars' performance abilities, the rally itineraries and lack of crowd control at events. Immediately after the deaths of Henri Toivonen and his co-driver Sergio Cresto in the 1986 Tour de Corse, the FIA banned the group from competing in the WRC from the following season, also dropping its prior plans to introduce Group S whilst designating Group A as the top class of rally cars with engine limits of 2,000 cc and .
In the following years, ex-rally Group B cars found a niche in the European Rallycross Championship until being dropped in 1993. By 1991, the World Sportscar Championship had moved on from Group B and C, with the GT championships formed in the 1990s preferring other classes such as the new GT1. The last Group B cars were homologated in 1993, though the FIA made provisions for national championships and domestic racing until as late as 2011.
Overview New FISA groups
In 1982, the Fédération Internationale du Sport Automobile (FISA) restructured the production car category of Appendix J of the International Sporting Code to consist of three new groups.
The outgoing Group 1 and Group 2 were replaced with Group N and Group A, for unmodified and modified production touring cars respectively. These cars had to have four seats (although the minimum size of the rear seats was small enough that some 2+2 cars could qualify) and be produced in large numbers. Their homologation requirement was 5,000 units in a 12-month period between 1982 and 1992. From 1993, the requirement was reduced to 2,500 units.
Group B was for GT cars with a minimum of two seats, redefined as sports grand touring cars in 1986. It combined and replaced Group 3 and Group 4, two grand touring groups already used in rallying, and the production-derived Group 5 silhouette cars used in circuit racing. Group 5 cars had never been permitted in the World Rally Championship for Manufacturers.
Homologation The number of cars required for homologation—200—was 4% of what some other groups required, and half of what had previously been accepted in Group 4. As homologation periods could be extended by producing 10% of the initial requirement each subsequent year (20 in Group B's case compared to 500 for A and N), the group made motorsport more accessible for car manufacturers before taking the group's technicalities and performance into account. 'Evolutions' could be included within the original homologation without needing to produce a new initial run, allowing manufacturers to tweak various aspects of their competing car and produce 20 of the 'evolved' cars rather than 200. Together, these homologation rules resulted in Group B 'homologation specials'—extremely rare cars that were only produced to satisfy the homologation quota rather than for sales, if they continued to exist beyond presentation to FIA officials in the first place.
Group B could be used to homologate production sports cars which were ineligible for Group N or A due to not having four seats or not being produced in large enough numbers (such as the Ferrari 308 or the Porsche 911). Furthermore, the low production requirement encouraged manufacturers to use competition-oriented space frames instead of the unibodies typically used in most series-production road cars.
Existing cars already homologated within Groups 2, 3 and 4 could be transferred to Group B, with many being automatically transferred by the FISA secretariat.
Regulations
Specific regulations Group B followed Article 252 and 253, which covered such things as safety cages or parts defining a car, like windshields or side-view mirrors. Article 256 covered regulations specific to Group B, with 5 paragraphs over half a page, and included most of the 7 pages of Article 255 for Group A. The first two paragraphs of 256 covered the definition of "(Sports) Grand Touring Cars" with a minimum of two seats, and their homologation requirements.
The section, "3) Fittings and Modifications Allowed" states, "All those allowed for Group A..." referring to the base rule set of what is allowed to be modified, how it can be modified, and what can be removed from the homologation road cars. +Group B engine capacity, weight, and tyre width limits, 1982Maximum engine capacity (cc)Minimum weight (kg)Maximum tyre width (in)1,00058081,3006758.51,60075092,000820102,500890113,000960114,0001,100125,0001,23513>5,0001,30014 If forced induction is present, restrictions apply as though the engine capacity is 1.4 times its actual value. If the engine is a Wankel rotary or similar, then the capacity is considered to be "twice the volume determined between the maximum and minimum capacity of the combustion chamber." The equivalent capacity, , for a turbine engine is much more complicated, derived with the formula (1982) or (1986), where is the "high pressure nozzle area" (cm2), and / is the "pressure ratio" of the compressor.
Resulting builds
Ultimately, there were few restrictions on technology, design or materials permitted. For example, fiberglass bodywork was used in the Ford RS200, a car without a common commercially available counterpart, though silhouette race cars using space frame chassis were still common even when consumer car equivalents were mass produced, for example in the case of the Peugeot 205 T16 or Lancia Delta S4. The rules provided for manufacturers who wanted to compete in rallying with mid-engine and RWD or 4WD, but their RWD production models had been gradually replaced by FWD counterparts. By reducing the homologation minimum from 400 in Group 4 to 200, FISA enabled manufacturers to design specialized RWD or 4WD homologation specials without the financial commitment of producing their production counterparts in such large numbers.Mad For It, Mike Goodbun, Classic Cars, December 2006
When the Group N, A, and B rules were decided upon, weight and engine displacement restrictions were thought the only way to control speed. This meant that there were no restrictions on boost, resulting in power output increasing from the winning cars' in 1981 to there being at least two cars producing in excess of by 1986, the final year of Group B in rally.Chrysler Sunbeam Ti_and_Sunbeam_LotusLancia Delta S4 Turbocharged engines were not yet common in road-going cars and had only been introduced in the early 1960s, but in the early and mid-1980s, engineers learned how to extract extraordinary amounts of power from turbocharging. Some Group B manufacturers went further; Peugeot, for example, installed a Formula One-derived antilag system to their engine, although the technology was new and not very effective, and Lancia twincharged their Delta S4. Nowadays, the power output of turbo engines is limited via intake restrictors, and in the Groups Rally hierarchy, each class has an explicit weight/power ratio limit.
Across Groups N, A, and B, there were 15 classes based on engine displacement, with a 1.4 equivalence factor applied for forced induction engines. Each class had weight and wheel size limits. Notable classes for Group B were the 3,000 cc class (2,142.8 cc with forced induction) with a 960 kg minimum weight (Audi Quattro, Lancia 037), and the 2,500 cc class (1,785 cc with FI) with a 890 kg minimum weight (Peugeot 205 T16, Lancia Delta S4). The original Renault 5 Turbo had a turbocharged 1.4 L engine, so it was in the 2,000 cc class. Renault later increased the size of the engine somewhat for the Turbo Maxi to be able to fit larger tires (at the expense of higher weight). The Ferrari 288 GTO and the Porsche 959 were in the 4,000 cc (2857 cc with FI), 1,100 kg class, which would probably have become the normal class for circuit racing if Group B had seen much use there. +Group B subclassesFIA Regulations, Appendix J 1986, Art. 256 – Specific regulations for Sports Cars (Gr. B): http://www.fia.com/resources/documents/991499716__Hist_App_J_86_Art_256_a.pdf Displacement Weight Wheel width (front & back) Cars Naturally-aspirated Supercharged or turbocharged 4,000 cc 2,857 cc 1,100 kg 12" Ferrari 288 GTO, Porsche 959 3,000 cc 2,142.8 cc 960 kg 11" Audi Quattro, Lancia 037, MG Metro 6R4, Ford RS200 2,500 cc 1,785 cc 890 kg 11" Peugeot 205 T16, Lancia Delta S4 2,000 cc 1,397 cc 820 kg 10" Renault 5 Turbo
Rallying
1982–1983
The existing Groups 1–4 were still permitted in the World Rally Championship during 1982, the first year of the new groups. Although some freshly homologated Group B cars were entered from the first round in Monte Carlo, no car from the group made podium at any of the season's 12 rallies.
Although the Audi Quattro was still in essence a Group 4 car, it carried Hannu Mikkola to the driver's title in 1983. Lancia had designed a new car to Group B specifications, but the Lancia 037 still had rear-wheel drive and was thus less stable than the Quattro over loose surfaces. Nevertheless, the 037 performed well enough for Lancia to capture the manufacturers' title, which was generally considered more prestigious than the drivers' title at the time, with a win to spare. In fact, so low was Lancia's regard for the Drivers Championship that they did not enter a single car into the season finale RAC Rally, despite the fact that driver Walter Röhrl was still in the running for the title. This may have been, in part, because Röhrl "never dreamed of becoming a world champion."
The lenient homologation requirements quickly attracted manufacturers to Group B. Opel replaced their production-derived Ascona with the Group B Manta 400, and Toyota built a new car based on their Celica. Like the Lancia 037, both cars were rear-wheel drive; while proving successful in national rallying in various countries, they were less so at the World Championship level, although Toyota won the 1983 Ivory Coast Rally with Björn Waldegård behind the wheel.
1984–1985
In 1984, Audi beat Lancia for both the manufacturers' title and drivers' titles, the latter of which was won by Stig Blomqvist, but received unexpected new competition midway through the year. Peugeot had joined with its Group B 205 T16. Like the Quattro, the T16 also had four-wheel drive, but was smaller and lighter. At the wheel was 1981 driver's champion Ari Vatanen, with future Ferrari Formula One team manager and FIA President Jean Todt overseeing the operation.
A crash prevented the T16 from winning its first rally, but the writing was on the wall for Audi. Despite massive revisions to the Quattro, including a shorter wheelbase, Peugeot dominated the 1985 season, although not without mishap—Vatanen plunged off the road in Argentina and was seriously injured when his seat mounts broke in the ensuing crash. Fellow Peugeot driver Timo Salonen won the 1985 driver's title with five wins.
Although the crash was a sign that Group B cars had already become dangerously quick (despite Vatanen himself having a consistent record of crashing out while leading), several new Group B cars debuted in 1985: Late in the year, Lancia replaced their outclassed 037 with the Delta S4, which featured both a turbocharger and a supercharger for optimum power output.