Which head/combustion chamber is better for performance? Speed master aluminum LA or aftermarket magnum iron head?

dusterdoug said

I built a 416 years ago that went 10.14@130 through the muffs…with a flat tappet cam…and EQ heads.

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Can you elaborate on the specs please. Most 400 cube small block mopars usually run mid 10's with an OEM style head.