Thanks, but I'm pretty sure the quote BitPlayerVesti referenced before I posted my comment is the one I was thinking of. I should have read more of the thread first.
I'm not a huge fan of Earnie Shavers as an ATG heavyweight puncher, but considering he was only 210lbs in his prime he hit ridiculously hard. Compare him to any other cruiserweight (which is what division Shavers would likely fight in today) and I can't think of another fighter that heavy handed. Gassiev? Kudryashov? Ezra Sellers?