It's possible it was assembled that way, but it's not really common. Just because the heads have the same casting identifiers(camel humps, housetops, etc) doesn't mean they have the same valve diameters, or combustion chamber volume. By the same token, heads with
different casting identifiers could have the exact same valve diameters, and combustion chambers.
The only way to determine what heads you have is by the casting numbers. You'll need to pull the valve covers to see them, usually, tho sometimes one is visible thru the oil filler hole in the valve cover. You also need to check the casting
dates on the heads to see if they are compatible with the assembly date of the
engine.
Casting numbers will usually tell the tale. However.....it's always possible that someone has changed the valve diameter on small valve heads to the larger diameter valves, rendering the casting IDs useless.
Check the casting #s and dates, and let us know what you find. We can decipher them from there.
Adams' Apple2010-02-22 21:02:32______________
Joel Adams
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