No, you only need the hood. Even if the box they are trying to sell you seals up at the hole in the hood, that is not enought air for the diesel. The hood will supply cold air, but not a ram effect. Spool up will be quicker with an open cone filter, rather than a closed up box with a 4" hole in it. I belive the K&N and AFE come with a heat shield like the one pictured above.
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