If you do not realize what Ernest is showing you, he is turning the old style valve adjuster into a newer one like the one that is used on the New FX Power Plenum. What he is doing is removing/eliminating the internal long valve spring and making is so you can use a shorter externally accessible valve spring inside the valve adjuster. This way you can adjust the tension on the valve spring without having to open up or tear down the Impact. This will in turn allow you to modify the FPS by how easy or hard it is for the hammer to open the valve. You can also use different strengths of springs for more control. The heavier the spring the less the valve will open or the weaker the spring the more the valve can open. Also using the rubber ball will still allow you to keep the valve opening at a specified gap, so if you cannot slow down the fps with just spring tension you can screw the valve adjuster in until the valve rod hits the rubber ball keeping the valve from opening to far and giving you excessive FPS. Using a lighter spring on heavy bullets or large calibers will give you the extra power (FPS) needed. The heavy spring will keep the FPS lower so that when shooting light bullets or smaller calibers you can keep the FPS at slower speeds to keep the pellet stable. Hope I explained that correctly.
