I was able to get some time in the shop this weekend and used Jerry's method (Thanks Jerry) of measuring ring gap to determine taper. They are all between .006 and .007 for taper. I was able to borrow a bore gauge and the cylinders are out of round by .0005 to .001 when measuring in three spots top and three spots bottom. Unfortunately my digital calipers stopped working (murphys law) so i will be on the hunt for a micrometer to get an actual piston, and bore measurement. Against everyone's advice and knowledge I am considering just throwing a set of rings at this engine, as the intention of this truck is not to be a daily driver, and at best it will only get 500 miles a year. But that decision wont be made until i get an actual bore and piston measurement.
When I was cleaning the carbon out of the piston lands the second land had a octagon paper thin ring behind it, pictured below. Does anyone know what this is, and if it comes with a new ring set?
