like a .030 groove?? on the block the oil hole is matched the the head gasket but the head is small. how but of a drill should i go to clean up the oil galley in the head?? and go half way from the bottom and the other half from the top? thx
I don't open up the oil passage in the head, or block. I just use a "cutoff wheel" in a die grinder, and grind a groove, the width of the wheel and about .030 should be good, on the cam. The first one I did, I went too big on the groove, and was flooding the valve train. So I just removed the rocker shaft, and drilled/tapped the oil passage in the rocker stand, for a "allen" pipe plug, with a hole drilled in it for a meetering orifice. Now I drill/tap all my heads, while prepping them, just in case.
