Barber Motorpsorts Park, Birmingham, AL May 20-21, 2017 Ralf Kuehnhoefer’s 1971 Chevron B19 chases after Gray Gregory’s 1977 Chevron B39.Photo: Chuck Andersen David Smith (1979 Porsche 935) leads Bill Keith’s 1973 911.Photo: Chuck Andersen James Roberts raced his 1966 Lotus 47. Photo: Chuck Andersen Open-wheel action with Richard Mitchell keeping his 1977 Crossle 30F ahead of Scott Robinson’s 1969 Winkleman WDF1 as John Breidenbach’s 1960 Lotus 18 trails.Photo: Chuck Andersen