Can you guess what we learned? Zilcho. As in zero difference anywhere in the power or detonation characteristics of the iron versus aluminum heads. ......... the dyno curves for the two styles of heads were identical. If anything, we could squint and guess and mumble that maybe aluminum heads were better by 2-3 hp. But the one thing we could never say is that the iron heads retained more heat and made more power than the aluminum.
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