Postby allencr » Sun Nov 23, 2014 7:45 am
The head and block absolutely NEED a clean&smooth&flat unpitted surface, machined, but only on that circle that the gasket's fire-ring sits on, about 3-4mm wide around the cylinder that they mate against.
Anything else is very secondary but does have to deal with some pressure, like the cams oil feed 70psi, coolant 20psi and the vent/oil drain with crankcase pressure/blowby, so a light smear of gasket cement/sealer can take care of them when the surfaces are marginal. If a few or more mm machined off won't fix the fire-ring area, it'll need to be heliarced/welded.
Yours looks like it'll cleanup with a sanding block & emery or wet&dry. Got a piece of very flat hardwood or a piece of marble from a trophy base or granite tombstone?