I worked on a 3.3 older buick park avenue or century, it shared similar if not the same block/heads/valve covers. Yes I know one does not simply assume such things but heck why not. Would there be, has anyone tried swapping head from a 33 to a 38? its been done many times on a 31 and 34 so why not maybe the same with these too? It seems like it could really add a bit of power if it were all ported out well. Thoughts? Comments Please? I think Im gonna look for one and check it out one my spare block I have.