The heat shield does nothing for anything except to warn you that the header is hot. It doesn't affect cooling, has no affect performance, and the only reason Honda has them on there is a safety measure. As in "don't touch the freakin header after you've driven the car for an hour". It serves no functional purpose what so ever as to how the engine or intake or cooling system runs. Even with the sheild on, the temp in there is the same. It's just got an extra part to heat up!