Everytime I read some1's way to perform an infinite, its wrong. Ive tried atleast 8 variations of iron man's infinite.
If u KNOW ne infinites, plz post it here.

The easiest way to do the infinite with iron man is by using psylockes anti air assist... while the other player is up on the air with psylockes assist jump and press lp,lp,lk,up+fp.....just keep doing this as many times as you want .... or you can do it when the enemy jumps and start an infinite..after the other player has taken enought hits you can do that pulse beam attack and then his only special or u can do the infinite then at the right time before he falls do the plasma cannon keep practicing till u master it

the timming is precise thouhg

u should do it like this

lp lp (slight pause) lk (regular pause) U+HP

when they get to high, do the lowpunches slower

if they get too low do lk lp lk hp