What is this air inlet?

[kipps]

I was browsing a local junkyard recently, and noticed that a couple of the late-model squarebody's, including a 1986, have this large plastic piece fastened to the radiator support. My 1987 does not have this piece, and instead, runs the air duct directly to a air inlet in the radiator support.

What's the purpose of this fancier air inlet? What is it called? How's it better or different from the simple setup that my 1987 came with?

The pic is a random one from google.

[TKCR]

That is how the tube ran from the radiator support, or grille, to the air cleaner. I’m not certain on this, but I believe all the trucks had them. They probably just got in the way at some point, or broken, and people tossed them.

[sick472]

My 85 attaches high on the core support, up at the top behind the grill. It has no piece like that, but is very factory looking. I would bet that piece attached low on the core support and then ran upward. This would allow road water to "fall-out" before getting sucked into the air cleaner.

I'm interested to know the real story...

[Just call me Sean]

'87 is the first year of fuel injection, so if it's the older ones that have it then that might be why. If the newer ones have it then maybe GM figured something out after the first year.

[Nick_R_23]

It’s a late year only part, around 86 or 87 is when it showed up, but not all trucks had them. It’s a water and debris trap, designed to filter out contaminants from the intake tract.