IMSA (International Motor Sports Association) : PROTOTYPE CHALLENGE ADDED TO 2015 CHEVROLET DETROIT BELLE ISLE GRAND PRIX October 31, 2014 By Tyler Hopper 0 SharesTweetSharePinShareThe TUDOR United SportsCar Championship Prototype Challenge (PC) class will compete for the first time on Detroit’s Race Read more here: Newspress 0 SharesTweetSharePinShare