This photo journal brought back some memories, and triggered a bit of a search for information. This Nike Missile base was a fairly easy exploration. The base is privately owned, and has been preserved in its abandoned / unused state for the most part.
This Nike Base was established to house and launch MIM-3 Surface to Air missiles. These were about 33ft long, and weighed 14.6t. The MIM-14's which succeeded the MIM-3's were capable of both Surface to Air and Surface to Surface engagements. Nike missiles could be fitted with both nuclear and conventional warheads. It is my understanding that the missiles located around Buffalo / Niagara, were fitted with mostly nuclear warheads, due to the areas importance.
The find of a 1970's era muscle car in the bunker, was an odd find indeed. There has been some speculation that this vehicle might have a connection to the unsolved 1974 murder of Karen Caughlin, from Sarnia, Ontario. The suspect vehicle was believed to be a Plum Crazy Purple dodge, which was fairly new at the time of the incident. I did try to email the OPP Investigator in charge of this case, about this find, but have not heard back.