As a viewer, don't think I should research where an engine came from. May be an interesting thing for him to mention though. The thing that bugged me was the discussion about the heads, great to point out the difference, he implied they are essentially the same. Not so. Completely different intake ports, his combustion chamber #'s are the NHRA spec, nowhere near actual CC's, his flow numbers way optimistic and unlikely to be equal given the difference in head design. Didn't comment on the cam as obviously aftermarket, with the three bolt configuration. His comments about valve spring color are worthwhile, that they are different, some stock are red, not sure about blue meaning. Good comment about identifying how the bottom end had been balanced.