The armor increases Chief's strength by 3x I believe. Chief without armor was able to dismantle trainers in exoskeletons that were 2 tonnors.
Also given his recent fight with John Steele, Cap's fighting skills won't be a major advantage over a stronger, arguably faster and more durable character
I'd say Chief wins, Cap's going to have a hard time hurting him, although he could potentially win with a few good shots with his shield, Chief isn't going to simply stand there and let Cap pound on him with the shield.