you mean in a p4p sense right, if not then there are only a few HW's to chose from. I don't even know how one can determine one true strength. there are so many different muscle groups that determine ones strength
Randall "Tex" Cobb was a freak of nature in the strength department. Larry Holmes on Cobb "He could get a job in the Army, not working on tanks, but being a tank". More on Cobb from Holmes " During stampedes, He's so strong he doesn't call the cattle in, he carries the cattle in". And last but not least, Holmes again on Cobb "He [Cobb] doesn't use wheelbarrows when working in his garden". Holmes added, "He uses an El Camino car". Cobb finished by saying "The mf'er grips the rear bumper and doesn't look to see if the [parking] brake is on, he just pushes the damn thing--filled with dirt--, on two wheels, to his garden".
Foreman, Tua, Lewis, Liston, Hagler, Leonard( he has underrated strength, see he was pushing Hagler), Marciano, Mayweather Jr( he has strong Functional Strength), Chavez Sr....