Marlboro 300 Trans-Am coverage from SCCA's Sports Car magazine. (Jon Mello Collection)
This race was unusual in the fact that the under-2 liter cars ran a separate 300 mile race on Saturday
while the over-2 liter cars ran in their own separate race on Sunday. Previous races had both classes
running together. Many drivers ran in both races as co-drivers to each car's regular driver. It was not
until the 1970 season that SCCA permanently removed the U-2 cars from running with the O-2s.