I think your right. The po told me "pro tech" so I assumed promaxx but more likely they are procomp. . .I was hoping they are promaxx because it seems like promaxx has larger CC
the promaxx has the larger combustion chamber because it's a copy of the edelbrock RPM head which is the 84cc chamber.
the heads you have are the smaller heart shaped chamber that's either 74 or 78cc, the ledge on the intake manifold mating surface of the head indicates it's the Victor head copy, not the RPM head.