Aren't the rochesters notorious for warpage too? I'm just repeating what I read, but the logic made sense when I read it. Something to do with the number of screws on the housing vs a Carter w-1... I just sent my Rochester off to
Be rebuilt. It's always run pretty good I thought, but I've never had anything else.
Good luck, I'm sure the experts here will figure it out for you. Amazing wealth of knowledge here.