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another factor is the bore size relative to the valve size and placement.

440s dont open on center but the smallblocks due iirc.
valve shrouding comes into play.

big or smallblock aside,

the largest bore with the most advantageous valve location with the most cycles going thru it will be the better performer when comparing equal size pumps.

Its all about passing the most air. Imo

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on the passing air concept. Everything else is just a "pathway" into the cylinders. Some designs are more "frictional" to the airflow than others. In light of your "large bore" theory, which is well-documented , the theory of a "longer" cylinder
stroke which increases the volume at LESS operating speed, holds truth too!!