So I really want to make an iron man mark 3 suit that is proper size, 6 ft 3 in according to marvel's site, however I've got no clue on the original helmet size, any help?
according to the comics tony stark is 6 foot the suit makes him 6.2-3 now if the suit is 6.2 we can presume that the helmet is 1/8th the size of the full body (basic human are usually 8 times their head size in total height) so odds are the helmet is 9.25 inches tall and width can be found from looking at a pic then!
That may be off but from that height thats at least the human head average, if you want it super accurate get a full scale pic and check the whole size as 6.4 and then do teh math based on the lid size!