| Event | Year | Start | End | Races | Teams |
|---|---|---|---|---|---|
| Pre-Worlds & North American Championship | 1998 | 12 Sep | 17 Sep | 6 | 90 |
| North American Championship | 1997 | 05 Jul | 11 Jul | 8 | 35 |
| North American Championship | 1996 | 07 Aug | 10 Aug | 7 | 34 |
| North American Championship | 1995 | 27 Jul | 04 Aug | 6 | 26 |
| North American Championship | 1994 | 01 Jan | 01 Jan | 6 | 35 |
| North American Championship | 1993 | 30 Aug | 03 Sep | 5 | 31 |
| North American Championship | 1978 | 01 Jan | 01 Jan | ||
| North American Championship | 1968 | 01 Jan | 01 Jan |