Ep 57. Iron vs. Aluminum Heads: A Study of Heat 

All else equal, which will make more power, an iron head or an aluminum one? That's what we're testing on this week's Engine Masters, presented by AMSOIL. Aside from the obvious weight savings, there are some real things to consider. Does aluminum's ability to shed heat help it make more power, or does the iron head's heat retention promote cylinder pressure and therefore more power?