Schedule
| Rnd | Race | Length | Circuit | Date |
|---|---|---|---|---|
| 1 | Superflo 12 Hours of Sebring | 12 Hours | Sebring International Raceway | March 22 |
| 2 | Toshiba Nevada Grand Prix | 3 Hours 45 Minutes | Las Vegas Motor Speedway | April 26 |
| 3 | The Dodge Dealers Grand Prix† | 1 Hour 45 Minutes | Lime Rock Park | May 25 |
| 4 | Sports Car Grand Prix of Road Atlanta | 3 Hours 45 Minutes | Road Atlanta | June 21 |
| 5 | Mosport Festival | 2 Hours 45 Minutes | Mosport | August 9 |
| 6 | NAPA Sebring Classic | 3 Hours | Sebring International Raceway | September 20 |
| 7 | Petit Le Mans | 10 Hours or 1000 Miles | Road Atlanta | October 10 |
| 8 | VISA Sports Car Championships | 2 Hours 30 Minutes | Laguna Seca Raceway | October 25 |
† - Two separate races were held for Lime Rock: One for WSC, one for the GT classes.
Read more about this topic: 1998 IMSA GT Championship Season