273 copper head gaskets SCE

the machine shop said they took off .003 to make the heads straight and both the machine shop and I did the feeler gauge with a straight edge which showed no reason to leak . when I told him I used 40 year old nos head gaskets he said the material break down. and I even seen a video on youtube the showed what happens when the material breaks down between the water jackets . just what happened to mine . .. IF that wasn't the case then it was a torque issue .

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