Big Ron was a tremendous puncher but I voted for Iron Mike.However the gap between these 2 guys re their punching power is not as wide as some fans would say.
Lyle may have hit harder punch for punch, but Tyson was much faster and had more in his arsenal by way of setting up attacks.
Lyle just didn't knock out good fighters. If you were ranked, you survived him, he couldn't knock good guys out. Michael Spinks is one of the greatest fighters to draw breath and it seemed briefly that Mike Tyson had killed him.
Not sure who had more raw power. Foreman had all kinds of praise for Lyle's power and insisted it was up there with the best shots he ever took. Bugner and Caldwell also praised Lyle. Tyson had crazy power, but it's odd that so many opponents such as Tillis, Thomas, Holyfield, etc stated that he wasn't the hardest puncher they faced. Gun to my head, maybe Tyson did hit harder (at least in combinations) due to his insane acceleration, odd angles, and superior technique. At the very least, Tyson was the more effective puncher and the better finisher. Lyle could hurt just about anyone, but when someone offered resistance in the form of superior defense or spoiling tactics, he came up short. Tyson's power was consistently effective no matter the level or style of the opponent.