NASCAR began its preparations for the first Cup Series race on dirt in 1970 with a full day of practice at Bristol Motor Speedway. The concrete track was covered in dirt for this experiment and the Cup Series and Truck Series had two practices each on Friday. The drivers were thrilled at the start of the day racing on the unfamiliar track surface but ended the sessions concerned about tire wear and what the rain expected to hit Bristol could do to the Tennessee red clay.
