Auto Club Revolution offers single player and multiplayer racing that is free to play.
Here is the link to the game:
http://autoclubrevolution.com

For more information here is the link to the ACR fact sheet:
http://autoclubrevolution.com/en/news/article/1105/car-setup-and-racing-physics

Thanks so much to the people at G2PO.com for letting me know about this one.