Thermal barrier coatings are no different in the way they work than your house insulation ... throw enough heat or cold at it for a long enough period and eventually the temp will equalize. So if you're thinking of using a barrier coating on, say, a drag race motor I'd have to say that the motor wouldn't run long enough tpo make a difference. If you were to use it on a street motor then it would slow the absorbtion process but eventually that intake is going to come up to the same temp as other engine components. Furthermore the barrier works both ways ... while it takes longer for the heat to pentrate in, once its in it takes longer to radiate back out.