Myths abound regarding the differences between the thermodynamics of aluminum versus iron heads. The facts seem to indicate that identical aluminum and iron heads offer basically identical performance. Aluminum heads are lighter, saving weight (relatively high up on the engine), but iron heads are less expensive. Aluminum takes less time to port and is easier to repair if failures occur. A properly ported and designed head will produce more power efficiently than a poorly ported and designed head regardless of the parent material.