From http://www.autosport.com/news/report.php/id/62544:

March 29 Homestead
April 6 St. Petersburg
April 19 Twin Ring Motegi
April 27 Kansas Speedway
May 25 Indianapolis Motor Speedway
June 1 The Milwaukee Mile
June 7 Texas Motor Speedway
June 22 Iowa Speedway
June 28 Richmond International Raceway
July 6 Watkins Glen International
July 12 Nashville Superspeedway
July 20 Mid-Ohio Sports Car Course
August 9 Kentucky Speedway
August 24 Infineon Raceway
August 31 The Raceway at Belle Isle Park
September 7 Chicagoland Speedway