Anyway. jokes aside, what armor is Tony using. And what motivation?
Neither would aim to kill from the onset, but I dont think Naruto could take a solid hit from Iron man, but if he can get off a Tajuu kage bunshin in tie Iron man might be in troble, as I'm unsure if his armor could survive a hit from the Fuuton Rasengen Shuriken, though it might be enough to ward off an Oodama Rasengan or two.
I think it comes down to who gets in the first strike. I think Naruto is faster, though. However he wouldnt resort to FRS as a first shot. He spams clones though.