No, it's not going to noticeably lower operating temps.
What it would do is lower the temp of the air entering the intake, this is good because cooler air is denser therefore it holds more oxygen.
"But it does me no injury for my neighbour to say there are twenty gods, or no god. It neither picks my pocket nor breaks my leg." - Thomas Jefferson, Notes on the State of Virginia, 1782
Arguing with a truck driver is like wrestling with a pig in mud, eventually you realize the pig enjoys it.