Re: custom air intake mod *LONG*

[cyng <cyng@lamere.net>]

   I'm going to send this to the GLX list, Eric, since I'm sure
that someone there will either be able to make use of this or poke
fun at it. I would send it also to the Corrado-Club list, but
there's no way that there's room enough for this kind of thing in
a Corrado (as I well know from looking at my brother's '92 SLC).
   Okay, well, here goes.
   It's a simple (in theory) modification, and doesn't necessarily
do you any good except at higher speeds or in cooler weather ...
but SOME good done is better than none, right?
   Your stock airbox has this elbow tube which runs from the front
of the airbox into the side fender. There's a big hollow space up
there in the fender, kind of closed off by the fender itself, the
interior of the engine bay, the wheelwell, and a sort of plastic
panel/skirt which makes up its "floor." This is where your car
gets its air from. It's not the best of sources, all closed-off
like that, especially in a black car like mine where heat gets
trapped rather quickly on a sunny day.
   So I thought to myself, asking where the freshest air could
come from? The front of the car, of course - somewhere before
the radiator, somewhere before any body panels, somewhere like
the nose of the car. So I took a look. There's not much room.
One can't remove one's headlight for legality reasons. I'm no
good with saws and such for hacking out a bit of my front grille
and making it look nice. So I looked some more. What I found was
a series of holes along the bottom of the front side of the front
spoiler. There's a hole on either side below the blinkers which
has a sort of plastic grille over it. Behind these, on either
side, hide your horns. On the passenger's side, attached to the
little grille there, is your ambient air temperature thermometer.
   I didn't want to mess with removing a horn or moving that
thermometer, so I looked some more. In the centre of the stock
front spoiler are a few open holes, wide ones. They look good,
except for the fact that the radiator extends even that low, and
it sits right behind those holes. So forget those central ones.
Between, however, the little grille/horn ones and the central,
radiator-filled ones, is a pair of smaller holes. The one on the
driver's side, which is about 4" wide and 2.5" tall, is, obviously,
on the wrong side of the car. The one on the passenger's side, on
the other hand, is in a good spot. It's about 3" wide by 2.5" in
height, or so. Each is covered by a dummy panel, a thin plate of
plastic which clips into and out of place rather easily. Hmmm ...
   I'd heard of ram-air systems, and air scoupes and other such
kits, but had been unable to find any for purchase. The closest
that I could find was a front spoiler available from ND which had
these air funnels on either side where your foglights would go,
and all that this purportedly was for was to help cool the
radiator as well as the brakes. Nothing about any tubes to bring
this fresh air up and into the airbox.
   So I figured that I'd have to do it myself. Grumbles and such.
   Thus, I took out that passenger-side dummy panel and took a
peek. Lo and behold, there's a little room there. Not much! But
most of space behind the hole is open. A bit of the metal tube
which carries collant to/from the radiator is there, but not
much of it. I popped the hood and looked down, after removing the
airbox. Indeed, there is a tight route through there, between the
radiator and the alternator.
   I went to a nearby HQ and walked about, an idea in my head. I
would need an adjustible, metal clamp (the kind where you screw
in a screw to tighten the notched, metal band), some of those
plastic baggie ties where you stick one end through a square in
the other and pull it tight, some metal mesh, and a hose or tube.
   The clamp was easy to find. It's 3"-2" or so, and didn't cost
more than a couple bucks.
   The little plastic baggie ties were also easy to find, from the
electronics department. I found small, black ones (my car is also
black, so this was ideal). These are the little things that you
use to hold wires together, I suppose, and such things. One end
goes through a square in the other end, and the whole thing is
ridged, so that, because of a tiny tab in the square hole, you
can't pull the thing back through. Cheap, too.
   The wire mesh was pretty easy to find as well. I used some
"charcoal-black" aluminum screen - the sort you'd put in a window
in your house. I did look at the little repair patches, but these
were far too small for my purposes, and so I had to buy an entire
roll of the stuff. Eight to twelve bucks.
   The tube or hosing, on the other hand, was a pain to find. I
wanted something at least 2.5" on the inside diameter and not more
than 3" in outside diameter. I wanted something flexible enough to
be able to be squeezed through a tight space, but tough enough not
to collapse as cloth would. I wanted something that would stand up
to hot temperatures. This last worried me quite a bit.
   I know that my oil temps rarely see 230, but it CAN get damned
hot in that engine compartment. So, I looked for something tough.
On the other hand, after having driven around several towns all
day on a hot day in search of this elusive tube, I decided to
check just how hot things did get in that area of the engine bay.
Well, my car's a '95, and so it has an air pump. There's a small
tube (barely an inch in outer diameter) running from my airbox
down to my air pump. This little tube goes exactly where the tube
that I wanted to run would go - between the radiator and the
alternator. In fact, it's braced against the metal of the alt. I
don't know that you have this air pump, but, take my word for this,
this little tube isn't what you'd call heavy-duty. It's plastic.
It looks a lot like a vaccuum cleaner hose. And it stands up to
whatever temps are in that area just fine. After all of this
driving, too, that bit of metal coolant pipe down by where the
hole in the front spoiler is was definitely air temperature. No
risks there, either. These, added to the fact that it's right at
the front of the car, where all the fresh, cooling air is, made
me lower my standards a bit when I looked for the tube I wanted.
That air pump tube ... looked like a vaccuum cleaner tube. Hrm.
A vaccuum cleaner tube ... Yeah ...
   So, I scurried back up to the HQ in Portland, and looked
around some more. All of their plumping tubes (vinyl and such)
were too small, or else collapsable. Forget it. I went up to the
Home Depot in Westbrook. No luck there, either. I went to several
hardware stores. I went to a VIP. I went to a NAPA. I went to a
Parts America/Western Auto. None of these places had any flexible
air ducting.
   Back to HQ. I told an employee what sort of thing I was look-
ing for, and he brought me straight to a small vaccuum cleaner
section. Slap my palm to my forehead - there it was. A 6' replac-
ment hose, 2.5" in inner diameter, rated for heavy-duty,
commerical-grade vaccuum cleaners and rug shampooers. Perfection.
And only (!) $16.
   I ignored my wallet's complaints and bought it.
   Here's what I did - pardon my ramblings.
   I unplugged my fan, as a lot of this work involves the hose or
your hands touching the fan - ouch.
   I unclamped my air pump's little tube. I removed the air box
from the car.
   I unclipped the dummy panel covering the hole just inside of the
leftmost, grille-covered hole, behind which hides one horn and to
which is attached my ambient temp thermo. It has two clips on the top
which you press downwards on, then slide back, towards the rear of
the vehicle. It's a pain to work the little panel out from between the
front spoiler and the radiator, but it's possible.
   From the top, I ran the vaccuum cleaner hose down behind the front
of the engine bay towards the ground. This is a pain, because the fit
is tight. The hose goes down, behind the fan, in front of the engine
block.
   Once I had it low enough, about even with the hole in the spoiler,
I knelt down and, from under the car (you don't need a jack or lift
or stand), kind of pushed the end of the hose into the hole. It's a
big pain, getting this through, because the end of the hose will get
caught on any number of protrusions. You need to bend the hose some,
squish it a bit, to get it through and around these protrusions, but
it WILL fit.
   With a firm grip on this lower end of the hose, I pulled hard,
pulling more slack through from above. It's tight, like I said, but
it doesn't hurt anything to pull hard. The hose should be tough enough
to take some stress.
   With a good half foot of the hose sticking out through the spoiler's
hole, I went back to the top end of it to put it in its place.
   I forced the hose into a safe place. It squished it some, so it's
not a perfect circle in one slightly cramped place, but it's still got
the same interior surface area and still lets in the same amount of
air. I made CERTAIN that the hose was between the alternator's housing
and the front of the engine bay. It CANNOT touch the fan blades. It
CANNOT touch the drivebelt. Placement is very important, because, if
you didn't get it in just the right place (kind of to the left of the
air pump's tube, using that tube as a sort of guide), you could do
some serious damage to your fan or drivebelt through friction. Or worse.
   With the hose firmly lodged into place, away from the fan and the
drivebelt, I moved on to the more delicate parts.
   I eyeballed how much hose I would need to let it reach into the
airbox, then cut the hose at that point. This is about halfway, so
you need at least three feet of hosing to get the job done.
   I unscrewed the elbow tube from the airbox and set it aside.
   I put the bottom half of the airbox back into the car (leaving the
rubber doughnuts out for now - this is just for better fitting). I
fed the top end of my hose into the same hole in the airbox that the
elbow tube once had been attached to. The fit is imperfect, since the
hole in the front of the airbox is about 3" and the outer diameter of
my hose is about 2.75". So, you need to block some of this off.
   With the hose in the airbox's hole (kinky), I marked and then
punched two holes in the hose. Small holes. One hole went into the
hose right where the hole for the elbow tube's srew used to be. The
other hole went just below there on the hose, the two holes barely
half an inch apart. I then used a baggie tie to hold the hose tight
to the airbox by feeding it through the two holes in the hose and
the hole where the elbow tube's screw once was. I hope that that
makes sense - poorly worded.
   Anyhow, this leaves gaps, which, my being from Maine, I sealed
off with duct tape. You're not a true Mainiac unless you have duct
tape somewhere on your car.
   I put the airbox's doughnut rings back on, holding it in place,
then put the top half back on, and reaffixed all the hoses and such.
   I moved to the bottom of the hose and trimmed this, as well, so
that there was barely more than 2" of hose protruding out the hole
in the front spoiler.
   Then I cut out a square of the screen about 5" on a side.
   I wrapped this gently about the end of the extra length of hosing
that I had, to approximate a good fit, wrapping the corners around
the hose and such. I used scissors to trim the corners and the rest
of the excess off so that it only ran about 3" up the length of the
hose. It's something like wrapping a present.
   I slid the hose out from the screen, holding it in its shape but
never actually FOLDING the screen. Folding it would, later on, most
likely cause it to snap, as thin, metal wires like to do. The whole
thing was kind of malleable in my hand, but I managed to get it to
keep it shape.
   I then slid this cap-like shape over the tip of the bottom end of
the hose sticking out through the spoiler's hole. I fitted one of
the metal clamps around this whole thing, then began to tighten the
screw with my fingers, holding the whole thing together with the
other hand.
   When the clamp held the screen well enough to the hose, about an
inch or so up it, I got the screwdriver and tightened it more, so
that the clamp barely squeezed the hose in - a tiny indentation
could be seen from the inside of the hose. Tight enough, I figured.
   I pushed the whole thing into the car a bit, back through the
hole, so that barely an inch remained outside, and the clamp was
basically in line with the hole - not forwards nor rearwards of
it.
   I checked to make sure that my pushing the hose back into the
hole had not caused it to slip and come into contact with the fan
or the driving belt. It hadn't, since it's wedged in there pretty
tightly.
   That's about it. Everything is nice and tight. The car revs
freely, and gets fresher air at higher speeds - perhaps even slightly
compressed air from that sort of ram. The car's temperature stays
nice and low - I still haven't seen 230oF as an oil temp for over a
month (and I don't have an oil cooler or anything of that sort). My
air filter is a K+N drop-in - no big deal.
   What I'd LOVE to have been able to do is have a notch cut into
my hood and a kind of plastic or carbon-fibre boot fit there to
kind of plug into a sort of shute which would feed directly into
the airbox, as a number of recent Subarus have, albeit on the
passenger's side and not in the centre. Like I said, though, I'm
a clutz when it comes to constructing such things and having them
work, let alone look good, and I thought it best not to cut up my
hood in light of this fact. Oh, well.
   All in all, it works. It's low-profile, though it doesn't
necessarily look great, what with the duct tape and all. It's safely
wedged into place. No big deal.
   Now ...
   If any of you knows of a similar sort of air intake modification
kit that's available, please let me know. I'd love to have a more
professional-looking setup for my car. Or, if any of you is skilled
with constructing such a thing, why not give it a shot? I'd certainly
buy such a kit!
   Anyhow, pardon my long-windedness. Hope it wasn't too dull.
-Tom

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         /|     -=Thomas J. Boyer<cyng@lamere.net>=-     |\
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