How many of you have checked the condition of your cylinders when you were doing your head gaskets. I have two engines one with 255,000 and the other one has 285,000. Both of these engines still have the hone marks at the top of the cylinder bores where the top ring stops. The engine with 255,000 miles still has the hone marks at the bottom of the cylinder where the bottom ring is at the bottom of its travel. I have talked to some engine rebuilders and they talked about the bottom of the bore being egg shaped. They did not say if the hone marks were still present in the cylinders that were egg shaped. I would not think that you would have .0005 to .001 wear in a cylinder before you would rub through the hone marks in the cylinder. Anyone have a wider base of comparison with these engines. I have quite a spread of tools but not a bore gauge or bore scope. I would like to get other peoples experiences. I tend to think good hone marks, rering and not rebore?