I saw Tyson take some nice shots & stay on his feet but not an excellent chin. Ali's chin along with his heart get the nod. I guess the Cooper fight is the only fight I ever saw Ali in lala land from a punch.
As for a taking a huge punch and staying on his feet I'd say Tyson. Ali had the superior recuperative powers, though. Tyson was stunned a couple of times but still won (Bruno, Tucker), but he never managed coming back after being in a really bad way. Ali did.
Ali would "ride" with the punch, while Tyson would absorb the full impact. But even still Ali could take a far bigger shot than Tyson. Ali stood up to fearsome hitters, Foreman,Frazier,Lyle,Shavers, & never would have been kayoe'd by the likes of Buster Douglas.
Ali fought bigger punchers and survived more than Tyson did against lesser known punchers so its got to be Ali.
Ali didn't "ride" against Foreman. He was taking those bodyshots full on. In fact I would venture to say no other fighter could have absorbed that body attack. (it's funny some actually have the adacity to argue whether or not Ali was hit in that fight), he was. Having said that, anyone who could take Lewis's bombs for several rounds has my respect. They both have great chins with the edge going to Ali for his ability to take body punches.
I would venture that the ropes absorbed some of the impact from those punches. Foreman landed some terrifying shots to Ali's body, but Ali was prepared for them and had time setting himself. I think that, together with his great punch resistance, is how he could survive them. Foreman did probably ruin his kidneys, though. Miske claimed that a well trained fighter could take just about any punch to the body if he saw it coming and had time to set himself. Ali surviving the Foreman onslaught seems to vindicate this.
Well I've also seen fighters go down on bodyshots like they were shot. ODL immediately comes to mind. And I for one wouldn't want to be the one absorbing Foreman's best shots to the body, ropes or not.
I was refering to head shots not body shots. Anyhow Ali absorbed much of the impact with tha aid of the ring ropes & having his forearms in front for protection. Hence the nickname for that tactic "The Rope A Dope". Ali let Foreman bang away & tire himself out. That was Ali's strategy all along. & it worked flawlessly.