Any 1960's GTO, I don't think there ever was a 67 1/2 camaro, a 67 or a 68. The only car that I remember to play that half year name game was the 64 1/2 Mustang.
It depends as favorite to actually buy and own, or favorite car(s) ever produced. 1965 SHELBY COBRA 4000 ROADSTER 1954 Mercedes Gullwing