Group 5

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The Group 5 had an existing between the 1960 and 1981 rating group of touring cars , the changes ranged far from the production car. The regulations were defined by the then FISA , forerunner of the FIA , in Appendix J of the International Sports Act .

Definition

In Appendix J, at the beginning of the chapter "Group 5", the term "high-performance cars" appears. It is also mentioned that the vehicles must have all components that are necessary for participation in public road traffic. What was meant were indicators, headlights, brake lights, etc. Later the term "special touring car" became established .

Number of pieces and seats

Compared to Group 1 and Group 2 , the requirements were set low: equipped with two seats, at least 25 identical cars had to be built and presented for homologation. The outer shape, track width and wheelbase had to be identical.

engine

There was extensive freedom in the machining of the engine. So the displacement could be increased up to the upper limit of the displacement class, be it through a different number of cylinders, boring and / or increasing the stroke. The number and arrangement of the crankshaft bearings, the number and position of the camshafts as well as the arrangement and number of the inlet and outlet ducts were free.

The "turbo factor" was set at 1.4. A common trick of the manufacturers was to use an engine with 1400 cm³ displacement in order to drive in the class (division) up to 2 liters.

transmission

Only one number of gears was permitted, whereby the gear pairs were free for all gears; also for the axle drive. As a " simple variant ", a transmission with a different number of gears could be homologated. The condition was that it was " freely available in stores ".

Braking system

A distinction was made between drum brakes, disc brakes or mixed systems with drums and discs. The series system had to be retained. It also had to be ensured that the actuation of the brake pedal worked on all four wheels, in the event of a defect on at least two wheels on the same axle.

Suspension

The functional principle had to be retained. The following versions were distinguished under the functional principle:

  • MacPherson suspension
  • Wishbones
  • Semi-trailing arm (example: rear suspension of the BMW 1600)
  • independent swing axle suspension (example: rear suspension of Renault Gordini R 1135)

body

There was far-reaching freedom to make changes to the body: the fenders could be adjusted to enable wider wheels to be attached. Openings that were deemed necessary to cool the brakes or the motor could also be made. Aerodynamic devices (spoilers, wings) were allowed to be attached. The restriction was a maximum height of 80 cm " above the lowest point of the fully sprung structure of the vehicle. " (This meant the body.)

Minimum weight

In principle, the minimum weight had to correspond to the value shown on the homologation sheet. This in turn was also subject to the restriction that, depending on the cubic capacity, it could not fall below the following values:

  • Displacement from 600 - 700 cm³: 470 kg
  • Displacement from 700 - 850 cm³: 480 kg
  • Displacement from 850 - 1000 cm³: 500 kg
  • Displacement from 1000 - 1150 cm³: 510 kg
  • Displacement from 1150 - 1300 cm³: 525 kg
  • Displacement from 1300 - 1600 cm³: 550 kg
  • Cubic capacity from 1600 - 2000 cm³: 575 kg
  • Cubic capacity from 2000 to 2500 cm³: 600 kg
  • Displacement from 2500 - 3000 cm³: 650 kg
  • Displacement from 3000 to 4000 cm³: 725 kg
  • Displacement from 4000 - 5000 cm³: 800 kg
  • Displacement from 5000 - 6000 cm³: 875 kg
  • Displacement from 6000 - 7000 cm³: 950 kg
  • Displacement over 7000 cm³: 1000 kg

Compared to group 2, the weight in the class up to 1000 cm³ is 155 kg, up to 2000 cm³ 270 kg and up to 4000 cm³ 390 kg; that means that the cars in Group 5 were closer to the racing cars than the touring cars, just in terms of weight. The driving performance hardly differed either: on the 22.835 km long Nürburgring-Nordschleife, a Group 5 Ford Capri took just 8 seconds more than a Formula 1 car at the time with 7: 18.48.

history

After January 1, 1972, Groups 5 and 6 were merged into a single group under the name "Sports Cars - Group 5" with no minimum production.

From 1977 vehicles of group 5 were used in the German racing championship . The division was based on the cubic capacity and was greatly simplified: Division I over 2 liters and Division II up to 2 liters.

Another field of activity were long-distance races for sports cars, where the cars were nominally inferior due to the series origin, but certainly achieved top positions.

Well-known Group 5 cars

Individual evidence

  1. ^ Extract from the ONS manual 1971
  2. ↑ autonatives.de - website: Super production cars of Group 5 - when touring cars knew no limits. From: autonatives.de , accessed December 30, 2018 .