does the valve sick into the head with wear? I ask this because I am installing solid lifter cams. My heads have 1 mm oversize Ferrera valves. I wanted to shim the lash on the looser side to account for the valves sinking into the heads. I am using JUN valve springs which have slightly more valve seat pressure of 65 lbs than the Tomei springs. But at peak lift the JUN will have less spring pressure than the Tomei .