Aluminum heads and 63 vs 65cc chambers

All I want to know is if the Promaxx and Speedmaster 65 cc chambers are just a slightly larger closed chambers or an open chamber like the Edelbrock 65 cc chambers are.

The pictures on the respective websites don't clarify this. Promaxx shows an LS combustion chamber which just adds to the confusion. I messaged both vendors and haven't head back from anyone yet.

On a related note, the recessed spark plug on these heads looks like a machining process was skipped. I wonder it there's enough material in that area to spot face the plug hole to sink the plug deep enough to at least get the ground strap in the chamber?

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