I have angle-milled small block V-8 heads, taking off .100" at the spark plug side of the head to zero at the intake manifold, but I've never tried it on a stovebolt engine. I can't think of a reason it shouldn't work, as long as it doesn't change the valve geometry in some oddball manner. I assume you'd angle the head in such a way that the valve-to-piston clerarance wouldn't be compromised?
Jerry

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