Hello All, I need the Piston & Cylinder to get very accurate measurments with my tools. I have found over the years that not everyone knows how & will not measure items the same as the next person. In order to make the best ring possible I need to measure cylinder to make ring and bore gage to gap ring to .001 to .002 gap. With a difference of .001 measurement in bore meens either ring will not fit into cylinder or gap will be too big with loss of power. Manufactures don't make rings but job shops do and often times production is the name of the game rather than quality. I found factory rings arn't round, have too much tension which heats up engine too much, ring too loose in ring groove which is a loss of power and a worn ring groove in some cases. I make rings in lots of 10, hand lap to .001 smaller than feeler gage measurment of ring groove. Ring OD is exact cylinder bore measurment and the I have a special tool that snaps ring & I hand gap it to .001 to .002 of bore gage measurment. Hope that helps explain why I need to measure cylinder bore, ring land in piston, pin location & ring ID for proper clearance to bottom of ring groove land. Thanks Frank Bowman