ashtrak

I have always heard that breaking in a motor with coated headers is a no-no. Now does this apply with new coated headers or all coated headers. I would think if you use a used set of coated headers, Something that has been through a difference in tempertures that it would be okay to dyno a new motor with them but i would like to know before doing so or what would happen to them if i did. Thanks to all that reply