Going with Foreman cos looking at his age and conditions he was still able to KO a punch of guys. Frasier has some seriously unnatural power as well.
The question is too simple. Briggs said it best when he explained "there are different types of hard". He said Foreman hit harder than Lewis, obviously Lewis KO'ed him, Foreman didn't. Foreman probably had the most thudding power just from an arm punch of any known fighter. Lewis and Wlad are better punchers though, Lewis KO'ed Briggs, Wlad KO'ed Schulz, Foreman didn't and probably wouldn't have done so in another attempt.
Earnie Shavers. The common opponents of Shavers & Foreman all pick Shavers as the more powerful puncher.
My vote goes for Earnie Shavers. George Foreman has pointed out two fighters he said hit extremely hard, which were Gerry Cooney and Alex Stewart. Jack Johnson should be on this list, and I would personally also include Corrie Sanders. (Gerrie Coetzee hit like a mule also.)
I find it difficult to compare Louis to the modern HW's. Only 17 of Louis opponents would be HW's today. Gloves used to be lighter as well in the 1930's. Not sure how Louis would fare in later eras.
Um Shavers is generally considered to be the hardest puncher, but for me it's got to be Foreman. You can see that he does damage with virtually every single punch he lands, even jabs. Unbelievable that Ali was able to take that punishement without going down - you can see the results today.. Razor Ruddock and Tommy Morrison should also make the list. Wlad hits very hard too, unfortunately he doesn't let his hands go.
nope thats my opinion. ah 6.6 245pounds guy with 48 ko in 54 wins and 17 championship fights with only two guys in the championship fights who weren't knocked down or out. yeah that looks like he is one of the biggest punchers in history of boxing