Trans-Am
Starting in 1984, the SCCA Trans-Am Series held a support race during the Grand Prix weekend. The Motor City 100 was often regarded as one of the most important events of the Trans-Am schedule due to the increased television and sponsor exposure, made possible by the international broadcast of the Grand Prix. The Trans-Am race wasn't popular with the Formula One drivers though with the heavy and powerful Trans-Am cars with their huge rear wheels having a tendency to break up the track, already in a suspect state thanks to the heat of the summer when the races were scheduled. This often made the Grand Prix's a more difficult prospect due to drivers having to go offline on to the 'dirty' part of the road to avoid problem area's on the track surface.
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