We pulled the valve covers off so we could put the o rings on the vales in place of the umbrella seals. The valve springs are the same height as the springs we took off but they are allmost an inch and a halff across with an inner flat spring. The keepers on top of the valve are big ger than the o rings they dont even touch they just slide on bye. May these are big block springs and retainers. I have this on going oil and smoking on start up problem. I think these are wrong for the heads they work well it seems other than the smoke. John 