Intake valve seat angles

The valves are hardened and all you can do is clean them. DO NOT try and grind them or you will be replacing them.  The valve seats can be  re-worked, but you need two angled reems to do it. The valve guide can be reemed if you have the proper size reem and have some idea on how to do this. Doing either of these can ruin them if done wrong and then it will hurt your pocketbook. Things like this are covered in the Heavy Maint. classes.