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Article 252 - General Prescriptions


1.1 All modifications are forbidden unless expressly authorised by the regulations specific to the group in which the car is entered or by the general prescriptions below or imposed under the chapter "Safety Equipment". The components of the car must retain their original function.

1.2 Application of the general prescriptions The general prescriptions must be observed in the event that the specifications of Production Cars (Group N), Touring Cars (Group A), Grand Touring Cars (Group B) do not lay down a more strict prescription.

1.3 Material The use of a material which has a specific yield modulus greater than 40 GPa/g/cm 3 is forbidden for the making of all the parts that are free or homologated as a Variant-Option. This restriction does not concern the parts homologated with the standard vehicle. The use of magnesium alloy sheet metal with a thickness less than 3 mm is prohibited.

1.4 It is the duty of each competitor to satisfy the Scrutineers and the Stewards of the meeting that his automobile complies with these regulations in their entirety at all times during the event.

1.5 Damaged threads can be repaired by screwing on a new thread with the same interior diameter ("helicoil" type).

1.6 Any Group A car, homologated after 01.01.99, with the exception of kit variants, and competing in rallies must not be wider than 1770 mm. Group N cars may compete in their integral version.


2.1 Ground clearance No part of the car must touch the ground when all the tyres on one side are deflated. This test shall be carried out on a flat surface under race conditions (occupants on board).

2.2 Ballast It is permitted to complete the weight of the car by one or several ballasts provided that they are strong and unitary blocks, fixed by means of tools with the possibility to fix seals, placed on the floor of the cockpit, visible and sealed by the scrutineers. Application: Touring Cars (Group A), Grand Touring Cars (Group B) ; no kind of ballast is authorised in Production Cars (Group N). In rallies, however, the carrying of tools and spare parts for the car will be allowed under the conditions laid down in article 253.


3.1 Supercharging In case of supercharging, the nominal cylinder-capacity will be multiplied by 1.7 for petrol engines and by 1,5 for diesel engine, and the car will pass into the class corresponding to the fictive volume thus obtained. The car will be treated in all respects as if its cylinder-capacity thus increased were its real capacity. This shall particularly be the case for assigning the car to its cylinder-capacity class, its interior dimensions, its minimum number of places, its minimum weight, etc.

3.2 Equivalence formula between reciprocating piston and rotary engines (of the type covered by the NSU Wankel patents) The equivalent cubic capacity is equal to the volume determined by the difference between the maximum and minimum capacities of the combustion chamber.

3.3 Equivalence formula between reciprocating piston and turbine engines The formula is the following:
C = ( S(3.10 x R) - 7.63 ) / 0.09625
S = High pressure nozzle area - expressed in square centimetres by which is meant the area of the airflow at the exit from the stator blades (or at the exit from the first stage if the stator has several stages).
Measurement is done by taking the area between the fixed blades of the high-pressure turbine first stage.
In cases where the first stage turbine stator blades are adjustable, they must be opened to their greatest extent.
The area of the high-pressure nozzle is thus the product of the height (expressed in cm) by the width (expressed in cm) and by the number of blades.
R = The pressure ratio is the ratio of the compressor of the turbine engine.
It is obtained by multiplying together the value for each stage of the compressor, as indicated hereafter:
Subsonic axial compressor: 1.15 per stage
Trans-sonic axial compressor: 1.5 per stage
Radial compressor: 4.25 per stage.
Thus a compressor with one radial and six axial subsonic stages will be designated to have a pressure ratio of:
4.25 x 1.15 x 1.15 x 1.15 x 1.15 x 1.15 x 1.15 or 4.25 x (1.15) ^6 .
C = Equivalent cubic capacity for reciprocating piston engines in cm ^3 .

3.4 All engines into which fuel is injected or in which fuel is burned after an exhaust port are prohibited.

3.5 Equivalencies between reciprocating piston engines and new types of engines The FIA reserves the right to make modifications on the basis of comparisons established between classic engines and new types of engines, by giving a two-year notice from the 1st January following the decision taken.

3.6 Exhaust system and silencer Even when the specific provisions for a group allow the replacement of the original silencer, the cars competing in an open-road event shall always be equipped with an exhaust silencer complying with the traffic regulations of the country(ies) through which the event is run.
For all cars used in Rallies and unless the limits imposed by the local authorities are lower, the noise level on the open road must not exceed 103 dB(A) for an engine rotation speed of 3500 rpm for petrol engines and 2500 rpm for diesel engines.
The orifices of the exhaust pipes shall be placed at a maximum of 45 cm and a minimum of 10 cm from the ground.
The exit of the exhaust pipe must be situated within the perimeter of the car and less than 10 cm from this perimeter, and aft of the vertical plane passing through the centre of the wheelbase.
Moreover, adequate protection must be provided in order to prevent heated pipes from causing burns.
The exhaust system must not be provisional.
Exhaust gas may only exit at the end of the system.
Parts of the chassis must not be used to evacuate exhaust gasses.
Catalytic exhausts:
Should two possible versions of one car model be homologated (catalytic and other exhaust), the cars must comply with one or other version, any combination of the two versions being prohibited.
All cars equipped with a kit (VK) must be fitted with a homologated catalytic exhaust.
For all groups, all cars must be fitted with a homologated catalytic exhaust if this is obligatory in the country in which they are registered, unless the catalytic exhaust is not obligatory in the organising country, in which case it may be removed.

3.7 Starting on board the vehicle Starter with electric or other source of energy on board operable by the driver when seated in the seat.

3.8 Cylinders For non-sleeved engines, it will be possible to repair the cylinders by adding material, but not parts.


All cars must be fitted with a gearbox including a reverse gear which must be in working order when the car starts the event, and be able to be operated by the driver when he is normally seated.


Suspension parts made partially or entirely from composite materials are prohibited.


Wheels made partially or entirely from composite materials are prohibited.
Measuring wheel width:
The width is to be measured with the wheel mounted on the car, on the ground, the vehicle in race condition, driver aboard, at any point along the circumference of the tyre, except in the area in contact with the ground.
When multiple tyres are fitted as part of a complete wheel, the latter must comply with the maximum dimensions for the Group in which these tyres are used (see article 255.5.4 and article 256.5).


7.1 Convertible vehicles must comply in all respects with the specifications applying to open cars.

7.2 Minimum inside dimensions If a modification authorised by Appendix J affects a dimension stated on the homologation form this dimension may not be retained as an eligibility criterion for the car.

7.3 Cockpit Only the following accessories may be installed in the cockpit: spare wheels, tools, spare parts, safety equipment, communication equipment, ballast (if permitted), windscreen washer water container (Touring Cars (Group A) and Grand Touring Cars (Group B) only). The passenger area and seat of an open car must in no way be covered.
Containers for helmets and tools situated in the cockpit must be made of non-inflammable material and they must not, in case of fire, give off toxic vapours.
The original fitting of the air bags may be removed, without modifying the appearance of the bodywork.

7.4 All body panels of the vehicle must be at all times of the same material as those of the original homologated car and must be of the same material thickness as that of the original homologated car (tolerance ± 10 %).

7.5 Headlamp mounting and protection The boring of holes in the front bodywork for light brackets is authorised, limited solely to mountings. In rallies, non-reflecting protectors made from flexible material may be mounted on the headlamps ; they must not protrude forwards beyond the headlamp glass by more than 10 cm.

7.6 Any object of a dangerous nature (battery, inflammable products, etc.) must be carried outside the cockpit.

7.7 Mud flaps (in Rallies only)

If the supplementary regulations of the event authorise them or impose them, transversal mud flaps will be accepted under the following conditions:
- They must be made from flexible material.
- They must cover at least the width of each wheel, but at least one third of the width of the car (see drawing 252-6) must be free behind the front wheels and the rear wheels.

- There must be a gap of at least 20 cm between the right and left mud flaps in front of the rear wheels.
- The bottom of these mud flaps must be no more than 10 cm from the ground when the car is stopped, with nobody on board.
- In vertical projection, these mud flaps must not protrude beyond the bodywork.
Mud flaps to prevent splashing towards the front, made from flexible material, may be installed at the front of the vehicle, if the supplementary regulations of the event authorise them or impose them.
They must not protrude beyond the overall width of the vehicle, or beyond the original overall length by more than 10 cm, and at least one third of the width of the car must be free in front of the front wheels.


8.1 Lighting A fog light may be changed for another light, and vice versa, provided that the original mounting remains the same.

8.2 The mounting of the alternator is free.

8.3 Horn In rallies only, the noise level produced by the horn must be greater than or equal to 97 dB during at least 3 seconds, measured 7m in front of the vehicle.


9.1 The fuel must be commercial petrol which comes from a service station pump, without any additive other than that of a lubricant on current sale. The fuel must comply with the following specifications:
- 102.0 RON and 90.0 MON maximum, 95.0 RON and 85.0 MON minimum for unleaded fuel.
100.0 RON and 92.0 MON maximum, 97.0 RON and 86.0 MON minimum for leaded fuel.
The measurements will be made according to the standards ASTM D 2699-86 and D 2700-86.
- Specific gravity between 720 and 785 kg/m 3 at 15°C (measured according to ASTM D 4052).
- A maximum of 2.8 % oxygen (or 3.7 % if the lead content is less than 0.013 g/l) and 0.5 % nitrogen by weight, the remainder of the fuel consisting exclusively of hydrocarbons and not containing any power-boosting additives.
The measuring of the nitrogen content will be carried out according to the standard ASTM D 3228 and that of the oxygen content by elemental analysis with a tolerance of 0.2 %.
- Maximum content of peroxides and nitrooxide compounds: 100 ppm (ASTM D 3703 or in the case of impossibility UOP 33- 82).
- Maximum lead content: 0.40 g/l or the standard of the country of the event if it is lower (ASTM D 3341 or D 3237).
- Maximum benzene content: 5 % in volume (ASTM D 3606).
- Maximum Reid vapour pressure: 900 hPa (ASTM D 323).
- Distillation at 70°C: 10 % -47 % (ASTM D 86).
- Distillation at 100°C: 30 % - 70 % (ASTM D 86).
- Distillation at 180° C: 85 % minimum (ASTM D 86).
- Maximum final boiling point: 225°C (ASTM D 86).
- Maximum residue: 2 % volume (ASTM D 86).
The fuel being accepted or rejected according to the standard ASTM D 3244 with a confidence limit of 95 %.
For vehicles with a catalytic converter, leaded petrol is forbidden.
If the fuel available locally for the event is not of a sufficient quality for use by competitors, the ASN of the organising country must ask the FIA for a waiver in order to enable the use of fuel not corresponding to the characteristics defined above.

9.2 Diesel

For Diesel engines, the fuel must be gas oil corresponding to the following specifications:
- Hydrocarbon level, % by weight 99.0 min.
- Specific gravity, kg/m 3 860 max.
- Cetane number (ASTM D 613) 55 max.
- Calculated cetane number 55 max.
(ASTM D 976-80)

9.3 Only air may be mixed with the fuel as an oxidant.

9.4 Refuelling procedure Standardised coupling - In case of a centralised system provided by the circuit or a system provided by the competitors, the refuelling hose shall be provided with a leak-proof coupling to fit the standardised filler mounted on the car (in accordance with drawing 252-5; the interior diameter D must not exceed 50 mm).

- All cars must be provided with a fuel filler complying with this diagram.
This leak-proof fitting must comply with the dead man principle and must not therefore incorporate any retaining device when in an open position (spring-loaded, bayonet, etc.).
- The air vent(s) must be equipped with non return and closing valves having the same closing system as that of the standard filler and having the same diameter.
During refuelling the outlets of the air-vents must be connected with the appropriate coupling either to the main supply-tank or to a transparent portable container with a minimum capacity of 20 litres provided with a closing system rendering it completely leak-proof.
The venting catch tanks must be empty at the beginning of the refuelling operation.
In the cases where the circuits are unable to provide the entrants with a centralised system, they will have to refuel according to the above procedure.
The level of the reserve tank may in no case be more than 3 metres above the level of the track where the refuelling is effected.
This applies to the whole duration of the event.
The overflow bottles must conform to one of the drawings 252-1 or 252-2.

The reserve tank and all metal parts of the refuelling system from the coupling over the flow meter up to the tank and its rack must be connected electrically to the earth.
The application of the following is recommended:
1. Each pit should be equipped with two aircraft type grounding connections.
2. The refuelling system (including tower, tank, hose, nozzle, valves and vent bottle) should be connected to one of the above grounding connections for the entire duration of the race.
3. The car should be connected, at least momentarily, to the other grounding connection as soon as it stops in the pit.
4. No fuel hose connection (fill or vent) unless and until conditions 2 and 3 have been fulfilled.
5. All fuel-handling pit crew members should wear non-static protective clothing.
The refuelling tank may be one of the following:
- models made of rubber, of the type FT3 or FT3 1999, built by an approved manufacturer, or
- tanks conforming to one of the drawings 252-3 or 252-4.

Application: For Touring Cars (Group A), Grand Touring Cars (Group B), refer to the general prescriptions of the FIA Championships.

9.5 Tank ventilation It is authorised to equip a tank with ventilation exiting through the car roof.

9.6 Installation of the FT3 or FT3 1999 tank The FT3 or FT3 1999 tank may be placed either in the original location of the tank or in the luggage compartment. There must be an orifice to evacuate any fuel which may have spread into the tank compartment. The position and the dimension of the filler hole as well as that of the cap may be changed as long as the new installation does not protrude beyond the bodywork and guarantees that no fuel shall leak into one of the interior compartments of the car. If the filler hole is situated inside the car, it must be separated from the cockpit by a liquid-tight protection.


Carbon brake discs are forbidden.

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