TTI Header “ break in “ thoughts

You can break them in on the engine. Done many of them.

TTI says that because people have little experience breaking in an engine. They set the timing to factory specs and the exhaust runs hot. Setting timing as if they were running it in the car under normal condition and broken in already. They don't want to deal with the warranty issue from user error.

The key is to get the engine fired and put 40* of timing in it. 2000 rpm with 40*. If you vary the RPM between 2000-2500, make sure the minimum timing is 40*. No load and the engine won't care. Exhaust will be cooler and not mess up the coating.