I own an F22B2 engine, im looking at some different valves, there are some that are stock size, then 1mm over, wondering anything needs to be done to use the 1mm oversized valves, and either way, what are the benefits/cons of using stock or oversized valves in an engine with just over 200k miles? thanks in advance

 

A good machine shop will be what you need for rebuilding the head.