High Quality Content by WIKIPEDIA articles! The 1998 Professional SportsCar Racing Championship season was the 28th and final season of the IMSA GT Championship. It consisted of an open-cockpit World Sports Car (WSC) class of prototypes and Grand Tourer-style racing cars divided into GT1, GT2, and GT3 classes. It began March 22, 1998 and ended October 25, 1998 after eight rounds.