InTheZone Racing Forums
Includes forums for NASCAR, F1, IndyCar, CART, and off road dirt.
invisionfree.com Details

Motorsport Forums
Discussion of every form of racing.
www.motorsportforums.com Details

Racing Message Boards
Includes discussions on sprints, stock cars, midgets, enduros, karts, dwarfs, vintage racing and drag racing.
www.4m.net Details

Speed Society
Focused primarily on racing topics such as drag, autocross, and road racing. Also covered are shows, automotive trends and the automotive aftermarket. Includes forums for general topics, current events, and news as well.
speed-society.com Details