Drilling holes in airbox

[dmiller@iea.com (Doug Miller)]

>I was wondering what is the proper way to drill holes in the airbox. I
>have a 4-cyl. '88 90, and I am looking for any way to make it faster.
>Will drilling the airbox make any difference? Does anyone know of any
>performance upgrades for my car?
>
>thanks for your time,
>
>        j. dade
Use caution on this type of modification.  Air movement through an
automotive induction system is quite fast, particularly at the high RPM's
where you are looking for your performance improvement.  The upshot of this
is that manufacturers spend considerable time designing this part of the
system, including the airbox, to shape the airflow and manage the "pulses"
of air that occur during induction. If you randomly drill air holes into
your airbox, you stand a good chance of creating turbulence that will
actually create MORE resistance to induction.  One of the most common signs
of this turbulence is noise, which takes energy to create, and energy
expended this early in the induction process impacts the entire intake
system.

To point out the potential fallacy of carrying this out, consider that if
it were that easy to create more power, the manufacturer would have put the
holes there in the first place.  Few issues are that simple, and this is
one of them.

My suggestion is to consider an engineered part like a K&N low resistance
filter, though I have no experience with them.  At least (presumably) these
parts were engineered to work with your induction system and have been
designed with the intake parameters in mind.

my 2 cents...