Is there a corrosion problem with cast iron blocks and aluminum heads?  The anodic index numbers between cast iron and aluminum is fairly close but they are not the same.  High strength steel numbers are further away from aluminum.  If there is a problem how do we address it.  Special coolant, special head bolts, special gaskets or something else.  Does a copper radiator cause a problem?  The question popped up on a road trip to look at couple of barn finds and I couldn't answer it. The answers will help me pick a radiator for my F-100.