Also for what it is worth, I agree with the Motec guys. Properly tuned, an engine will be slightly rich. As you lean it out and approach a stoichiometric mixture a.k.a. “lean best power” temps climb, once leaner than “lean best power” temps fall off. You never want to tune for “lean best power” because in that state of tune pistons are ready to melt,
oil will break down, cylinder walls scuff, and heads can crack.
Scott