The group N denotes the FIA Motor Sport a particular stage of processing of passenger cars from the 1980s until today.
- 5.1 camshaft, exhaust and engine management
- 5.2 springs and shock absorbers
Processing stage and regulations
These processing stages were divided by the FIA - and for group N, A, B, etc. Of these groups, the group N is the " mildest " tuning level. In the next freer group A, all series parts may be edited. This means that in the Gr. N all rights not expressly permitted by these regulations changes are prohibited. Also the external appearance of the vehicle remains unchanged. The fenders may not be modified. On the chassis of the exchange of shock absorbers and springs is permitted with certain limitations.
The technical output data are in Group A and N homologation. The detailed provisions for the group N are in Article 254 of the ISC of the FIA. The precursor of the N group was the group described in the regulations in force before 1
The provisions of the group N shall apply only to production cars must have 4 seats. The minimum quantity is 2,500 units in 12 calendar months. Delivery variants ( VN) group A ( touring car ) also apply to Group N (production cars). Specifications ( VO) of group A do not apply to the group of N, exceptions see catalog in the link below.
Within the group of N vehicles are divided according to engine capacity classes. In use today are the classes
- Up to 1400 cc
- About 1400 to 1600 cc
- About 1600 to 2000 cc
- About 2000 to 3000 cc
- 3000 cm ³
In previous years, until about 1980, a subdivision of the class up to 1400 cc was common. The engine capacity limits were 700 ³ 850, 1000, 1150 and 1300 cm. Because of the minimum number of pieces described above, for example, the cars of Carlo Abarth were not homologated in the series next class.
Validity of the homologation
The group-N homologation is performed by the vehicle manufacturer in FIA and optionally, depending on the time of manufacture of the type and other marketing and cost considerations, extended. The manufacturer must lodge also known as supplements to the original homologation, describe the subsequent trim levels and should be fully carried along with the homologation and the car pass to racing events.
After the Homologationsgültigkeit the homologation for vehicles in groups N and A for the DMSB area are automatically extended for another 3 years ( group DN and DA). Apply the currently applicable technical provisions of the group A and group N. The national group -A and N homologation valid across the whole DMSB area, with the exception of FIA-sanctioned competitions. A current list of currently valid homologation and maturities are available on the websites of the DMSB.
After the DN- homologation must be a Group N vehicle in either an "open class " as Group H switch, or, for example, after the DMSB created in 2006 new regulations in Division 6 of the historic CTC / CGT (Classic Touring Cars / Classic GT ) start (for Group N valid for model years 1982 to 1996 inclusive ).
These regulations will enable the launch of touring and GT cars, as they were in use in the years 1966-1996 ( the end of the DA -or N homologation ). Open to touring cars and GT cars, including the time in 1966-1996 in groups 1, 2, 3, 4, 5, N, A or B were FIA homologated (see Article 2). The vehicles have the then FIA regulations and comply with the following provisions have priority.
The N homologation are under No. 201 at a minimum weight. This is observed at all times and is preferably tested in the racing breaks. Ballast may be used; this is to declare and plumbing. The vehicle is measured " as is ", that is, with the current level of all fluids, but without a driver, helmet, etc.
- Clutch Disc
- Suspension springs with restrictions
- Shock absorber with limitations: the number must not be changed
- Rims; but these must correspond to the dimension of the homologation
- Tires; depending on the event possible restrictions
- Brake pads, hydraulic handbrake
- Seats; this must be the original ones or have a separate, time-limited homologation
- Fuel tank; this subject but then strict safety regulations
- Fuel and hydraulic lines
- All accessories exerts no influence on driving behavior, ie radio, sunroof, lights, steering wheel, depending on the tender, the exhaust system. Restrictions on the noise emissions are possible, depending on the event, such as at rallies by the traffic regulations.
Any rights not expressly permitted is prohibited edits. It may damaged parts are replaced with original parts. This can lead to a conflict when the camshaft is replaced. Whether she was really defective, at the racetrack, no one can verify, because defective parts are almost always discarded.
Camshaft, exhaust and engine management
The new camshaft to be incorporated is described with a certain accuracy in the Group N homologation. The art of engine tuner is now to find a camshaft that meets these mechanical dimensions, but can achieve a power increase.
In this regard it is important that (almost always), the exhaust system is optional, and the microprocessor in the electric motor control. By fine work with many test runs is with these three variables ( camshaft, steering, exhaust system) the power of the engine by 10 to 20 percent, even more increased in extreme cases. This is often the sound of the engine revealing. Stronger increases are possible in turbocharged engines because the boost pressure is controlled directly via the engine control. Today, a change of the maps in the control unit (ECU mapping ) is sufficient to change the characteristics of the motor from high speed to torquey powerful. Here, properties are mainly such as ignition timing and AFR maps (air / fuel mixture ) and the maximum charge pressure depending on engine load and speed ( " Turbo Dynamics Table", only for vehicles with exhaust gas turbo - charging) adjusted. In previous years, a change of camshaft was this necessary. When you increase the exhaust gas temperature, this still attracts adjustments to valves and pistons by themselves.
Springs and shock absorbers
Coilovers are allowed. Thus, a certain lowering is possible. The specified in the N- homologation measure No. 205: "Minimum height between the wheel hub and wheel housing " must be maintained within the tolerance limits.
A car of the group N is approvable with restrictions. The TÜV technical limit criterion is the sound level, measured under test conditions (not at maximum or rated speed, but sometimes even lower.) During subsequent operation at higher speeds, the nominal level is exceeded with safety.
Not allowed is the general road use on so-called slicks, ie racing tires, which is why Reifen-/Felgensätze be transported as checked baggage or the drivers on semi-slicks fall back ( with the EU-wide ECE approval mark ). Moreover, the ride comfort is limited and the noise, not only through the exhaust can be annoying. Nevertheless, there are primarily in the automotive slalom participants who come on their own wheels to the event. Most financial reasons are decisive ( trailer and towing vehicle omitted), but also on the pace of arrival is significantly higher than with a team.