In order to promote fairness among competitors, competitive events are divided into groups and classes.  For example, in speed events, a 1956 would not be in the same class as a 1974 or a 1992.  The class division is based on the equipment.  A solid axial Corvette  could not compete with a split axial Corvette in an autocross; however, on a road rallye, these two cars are equal.  In Speed Events, groups and classes ensure that the equipment is equal (as close as possible); the competition determines driver's skill.  It would not be fair for a 450 hp car to compete in the came class with a 350 hp car.  In addition to the classes based on equipment, in some events, classes are  further divided into women, men, and novelist.

Groups for Speed Events (brief overiew)

 In the interest of providing a fair and competitive Speed Event program, NCCC has divided the Corvette into separate Groups and Classes.  First the Corvettes are divided in four (4) separate Groups.  Depending on the amount of modifications made from the Factory condition,  the Corvette will be placed into one of the four (4) Groups starting with Group I-Street and progressively moving to Group I, Group II and Group III as the number of modifications increases.  The Groups  are then further divided in Classes.  The proper class will depend on the age (body style) of the Corvette and the engine being used.  Within Group III, some of the Class determination is also made by increasing  levels of modification starting with the MOD Classes and moving to the Race Prepared Class and then to the Race Prepared Altered Frame Class (RPAF).  Each level of competition also requires additional safety  equipment.  For example,  a Corvette that has had frame work performed to stiffen the frame would be placed in the Altered Frame Group;  Altered frame Group requires safety equipment that a Group I car does not require.  For in-depth information please consult the current NCCC Sanction Program rule book and talk to other who participate in the Competition program.

Groups for Concours (brief overiew)

 Corvettes entered in a Sanctioned NCCC Concours will be separated into one of six groups based upon the criteria for each Group.  A Group generally represents cars within a reasonable range of the same level of preparedness for a Concours.  These Groups provide a  level of competition that is both fair and reasonable for the entrants and the judges who must evaluate individual cars that are very different in age, design or state of modification and vary widely in the amount of regular usage.  The Concours Groups are  Concours Prepared Group (C/P), Modified Group (MOD), Street Show Group (S/S), Wash and Show Group (W/S), Race Prepared Group (R/P) and Custom Group (CUS).  Within each Group are the classes,  a concours prepared 1953 would not be judged with a concours prepared 1987.