What you want is the Devcon epoxy. I don't know if there is an epoxy iron that they make but the sure make epoxy aluminum.
I just don't know how adviseable it is to deport the iron heads with epoxy. Sure racers do this all the time on RACE engines.
How you GUARANTY that the epoxy doesn't come loose and the engine swallow it I don't know.
I would do what those guys recommended. Leave the iron 4v's alone and get another set of heads. What do a set of bare Aussie 2v's cost $350? Why bother to make your own?
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