the Bristol Motor Speedway is 0.533 mi long racetrack. The road is banked and circular. The straights are banked to 6–10° and turns to 26–30°. I have made a small diagram for ilustration.
Before the cars fully enter into the turn, they have to pass through a section of the track where the banking graually progresses from 10° to 30°. Does anyone knows how is determined the lenght of the road between two levels of banking?