Quote:

Has anyone ever had issues with the valve guides? A buddy of mine has these heads on a 383 with 1.6 rockers and a hyd. cam. His lift is right at .600" of lift. He used the springs that came with the heads with the upgraded retainers and locks. After 20 passes the valve guides were pounded down the valve stems.


Were the retainers hitting the guides?

In theory, there is no difference between theory and practice. In practice, there is.