i am pretty sure they had 327s in 63. i forgot about the 409 though. i don't think they put any 153, 230 or many 283s (those small v8s just couldn't cut the mustard) in c60s. my experience has been doesn't matter what the #'s say people will argue with you about what size it is till you measure the bore and stroke, if you are trying to sell it.
