After installing and torquing down the heads and setting the valve clearances, I rotated the enginne several times, then removed the heads to check the clay impressions...
In Cylinder #1 you can see the clay was well into the chamber and got just a small nick in it from the intake valve with no impression from the exhaust valve.
In the #2 Cylinder there was a more pronounced impression from the intake valve, but still none from the exhaust valve.
Since my clay was approximately 2.5 mm thick There should be more than adequate clearances for the valves.
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