| 5 | Portland R5 | 6/17/06 | Portland International Raceway | 23 | 25 |
| 6 | Portland R6 | 6/18/06 | Portland International Raceway | 18 | 24R |
| 7 | Cleveland R7 | 6/24/06 | Grand Prix of Cleveland | 16 | 25R |
| 8 | Cleveland R8 | 6/25/06 | Grand Prix of Cleveland | 16 | 13 |
| 9 | Toronto R9 | 7/8/06 | Toronto Street Circuit | 10 | 13 |
| 10 | Toronto R10 | 7/9/06 | Toronto Street Circuit | 7 | 16R |
| 11 | NASA Mid-Ohio R11 | 9/16/06 | Mid-Ohio Sports Car Course | 15 | 18R |
| 12 | NASA Mid-Ohio R12 | 9/17/06 | Mid-Ohio Sports Car Course | 16 | 10 |