Originally Posted by lewtot184
the alum the heads are cast from is soft. anything with a steel fire ring, wire or no wire, will mark the alum. the only material i can think of that may not mark the alum is dead soft copper.

Mopar used to sell copper gaskets for the aluminum head Hemis. I am sure for this exact reason

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