Hughes makes a roller lifter with a screw in/out center. You use a micrometer to measure the lifter you plan on running and then you can adjust the height of the lifter cup to match (with pre-load figured in) and then use that instead of swapping in checking springs.
That makes no sense, how does that tell you how far the valve is from the piston?
To me that sounds like a tool to use in place of a HYDRAULIC roller lifter so you can dial in/measure a cam without having to swap in a checking spring. Same thing as using a soild lifter ( or a welded up hyd.) in place of a hydraulic lifter on a flat tappet cam.
To check piston to valve you have to push the valve TOWARD the piston.
