For the 201, Smoky Mountain and Duck River swings, competing teams will be restricted to using Hoosier 1300, 1350, 1450, 1600 and 55-compound tires or American Racer 44-, 48-, 53- and 56-compound rubber. All of the tires will be required to punch a minimum ’40’ reading when checked with a durometer. For 201 Speedway only, the Hoosier 1425 compound will be allowed in addition to the above mentioned Hoosier compounds.