Groups 6, 10 & 12a

Group 6 – Select big bore production sports cars and sedans through 1972

Group 10 - Select GT sports cars, Trans-Am, Stock cars, select cars raced between 1973 and 1999, Trans Am and production based contemporary cars as raced from 1999 to five years from today's date or other cars as assigned

Group 12a - Post 1972 prepared cars, a combination of large and small bore cars