Intake Air Dam

[Brian K. M.]

As I was looking under the hood of my '04 2.5 naturally asperated
Outback I noticed an interesting feature. On the underside of the hood
there is an air dam that, when the hood is closed, appears to block a
significant portion of the intake. It is only a cheap plastic piece.
My question is what is this for?? My only guess would be to keep water
and debris from entering the air box? I'm a currently removing it on
mine and my families to test determine a link to fuel efficiency, but
I was wondering if any one else knew of these??

Brian

 

[busterb]

As I was looking under the hood of my '04 2.5 naturally asperated
Outback I noticed an interesting feature. On the underside of the hood
there is an air dam that, when the hood is closed, appears to block a
significant portion of the intake. It is only a cheap plastic piece.
My question is what is this for?? My only guess would be to keep water
and debris from entering the air box? I'm a currently removing it on
mine and my families to test determine a link to fuel efficiency, but
I was wondering if any one else knew of these??

Brian

I removed mine and actually noticed a drop in fuel economy (23 mpg
average). Put it back and went to a 24-25 mpg average. May or may not
be related. Car is a bit peppier with it in place. I have an 04 obw
with k&N filter in stock airbox and have been using mobil 1 10/30 for
the past 7-8k miles. I too thought WTF would they block the intake but
it dosent seem to do anything good or bad

 

[Chris Phillipo]

Subject: Intake Air Dam
From: (e-mail address removed) (Brian K. M.)
Newsgroups: alt.autos.subaru

As I was looking under the hood of my '04 2.5 naturally asperated
Outback I noticed an interesting feature. On the underside of the hood
there is an air dam that, when the hood is closed, appears to block a
significant portion of the intake. It is only a cheap plastic piece.
My question is what is this for?? My only guess would be to keep water
and debris from entering the air box? I'm a currently removing it on
mine and my families to test determine a link to fuel efficiency, but
I was wondering if any one else knew of these??

Brian

Chances are it actually routes the air into the airbox from some other
place. You'd have to be inside that japanese engineer's mind that day
to know for sure