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Old 12-17-2015, 10:16 PM   #43 (permalink)
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Originally Posted by MichaelRTJ View Post
Is this a serious question? A *warm* air intake? You'll be dumping in unnecessary fuel, and burning too rich. That'll lower your fuel economy, not raise it. Hot air is easier for your while to drive through due to the thinner air, but cold air gives denser, more oxygen rich air to your engine.
This is a mod that people swear by on here. I believe the main theory people go by is that it aids in atomization and vaporization of the fuel allowing it to burn more completely.

If you have a properly functioning ECU and O2 sensor, it shouldn't run rich because the ECU will lean out the mixture.

However there are other downsides to doing a warm air intake. One significant one is that it increases the temperature of the combustion gases and thus increases heat rejection to the cooling system. This leaves less energy in the combustion gases to be recovered as power. Another problem with increased temperature of combustion gases is it increases NOx emissions.

I have serious doubts that the positives will out weigh the negatives and only see a warm air intake as a means to warm up an engine quicker.
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