Originally Posted by DENCOUCH
Perhaps I learned the wrong lesson sometime ago, but it has been my held belief that the opposite is true.
A hotter plug than required is detrimental in that it retains heat which can lead to expensive problems in a motor. A plug that is in the too cold heat range fouls easier as the heat from the plug is transferred too quickly to the cylinder head.
With this reasoning, I would believe that it would be worse to have a "too hot" plug in a lean condition than it would be to have a "too cold" plug.
You are correct. I should have "proof read", not just "Spell Check".