Does anyone know if the head to block mating surface are different between the 10 and 11?
I think the only difference between the 10 and 11 was larger sleeves and larger intake ports/carbs. Web Cams shows the same grinds for both. Will find out.I started to try to answer your question, but perhaps your question was not clear enough.
Why would the mating surfaces between cylinder head and cylinder block be the same if the displacement is different? The only way they could remain the same is if the bore was the same and the increase in displacement comes from an increase in stroke. I don't know these engines well enough so I gave up.
What is that you are trying to accomplish here? It looks interesting.