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Discussion Starter #1
the 2nd picture is looking inside the AVO oil catch can
(AKA air/oil separator) from the outlet hole looking
towards the 2 inlet holes. it looks like this unit's
baffling could be functional.
please excuse the resolution.

internally , the 2 inlets are physically separated
from the 1 outlet by a welded in place 45 degree
4 inch long piece of aluminum that connects
to a folded 10 inch rigid perforated aluminum screen.
the sketch shows it better.

a beautifully constructed unit .
polished aluminum .
totally welded box.
all holes threaded .
welded attachment bracket .
has an actual drain plug.
comes with about 11 feet of 13mm
black fuel line hose.
blue plastic/nylon Tefen connectors .
approximately 6 inches long
x 6.5 inches high x 2 inches wide.

unfortunately no sight tube for amount
of oil level collected.
very sketchy hook-up instructions.
recommended installation in front of battery
is fairly well explained.

sorry for long post. i think i'll first try
a closed loop PCV-crankcase only
installation and see if it collects much oil.
i'll probably only use one inlet on the
oil catch can and plug the other .

purchased it at rallitek.com .
good price , knowledgable guys.
 

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Ahhhh...finally! I started installation on my AVO about a month ago. I opted to fabricate an aluminum bracket in an "L" shape and install the catch can between the passenger strut and the I/C, as there's a space that it fits in perfectly. So we fab a bracket, sand down the rough edges, primer it, and spray it flat black to match the engine bay....only to discover none of us are comfortable enough with the provided instructions to run any of the tubing! PLEASE could you provide a pic with what you believe to be the proper routing of the lines? It'd be tremendously helpful....
 

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I still say it is ridiculously overpriced even if it is well made. On the other hand, I returned a Cusco because it didn't have any baffling. I don't know what they expected it to "catch".

-st
 

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That is a good looking design...gives the oil a nice relatively cold surface to condense on. I'd still like to see a finer mesh than that in there.

I have my Perrin CC stuffed with a foam similar to what they use in couch cushions, along with a few patches of t-shirt material near the inlet to keep the foam relatively clean. Been working phenominally thus far.
 

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great photo layout...catch can looks pretty nice. mike up at rallitek is very helpful. and, i have the same cord-less mouse!
 

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Discussion Starter #6
what is/was your major in college? edit: stolen civic pics

the passenger strut tower location is also where i thought i'd try the initial install.
with the 2 factory threaded holes for a bracket like you've done it really seems to have good potential . should be easier than the battery location to drain the caught oil .
this location will depend on if i can connect to the pcv hose assembly with a pretty straight run or if it is too circuitous.

i am going to hold off on this project for a week or so until i install an oil pressure and oil temperature sender , that are presently in UPS's hands .

that will require pulling the intercooler and at which time i can figure out which spot on the pcv hose assembly to tie into. i'm going to only use 1 line off the assembly to the AVO with no additional lines T'd in .
then back from the AVO to the factory fitting on the air intake.
it seems there are only 3 spots to tie into :from engine to T; from T to manifold;or from T to air intake.

i've read the hundreds of search pages on this like everybody else. i don't think there's only ONE way to connect a oil catch can, it all depends on what you're trying to accomplish, what speed mods you've done. off road or licensed for the highway.if you're turbocharged, supercharged or naturally aspirated , what kind of engine you have and what mileage .
so i don't really have a schematic yet , but when i do i 'll post it .

my reasoning for only tieing into the pcv is to keep the emission system entirely stock . the oil catch could potentially lower my emissions (probably a dream) and might keep the STi running as well in the future as it does now .
the Colorado Clean Air program is rough . vehicles are run on dynos that check emissions at low and top posted speeds and under load. each year they tighten the emission standards . there are now remote testing units as you drive by they test your exhaust , and if your out of spec , your license plate is photo'd and you get a letter to come down and prove they shouldn't excessively fine you . i'm not against clean air, i like to do my part. we need to keep the air clear so we can always see the Rocky Mountains.

mike was also the guy that was helpful for me at rallitek.com .
 

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Discussion Starter #9
for a while I WAS confused with your observation .
that was good . keep it coming .

the hoses for the passenger side strut install line up well .
they'll be relatively short runs.

i think i'll initially connect the catch can between the T and the air intake.
that should minimize oil vapor/residue/sludge entering the
air intake-turbo-intercooler-throttle body at Heavy engine load .
this will hopefully keep the oil film down and possibly oil combustion
acting as an octane reducer with the resulting knock/ ping /detonation/
retard/power loss.


at Light engine load , i'm not too concerned about oil vapors
entering into the manifold for combustion.
i'm not really convinced that there's enough oil vapor
at Light engine load with an Unmodified engine to act as an
octane reducer .

but if the engine was heavily Modified with higher boost and
potentially more oil blow-by entering the manifold ,
that additional avenue of octane reduction could become be a real concern .
then i'd seriously consider installing the catch can between
the block and the T.

if my initial install doesn't collect some reasonable
amount of oil in relation to oil consumption during say,
the interval between a 3000 mile oil change
and assuming moderate amounts of heavy engine loads ,
i will then try this install between the block and the T.
 

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Discussion Starter #10
by the way , the strut tower factory holes are approximately
2 inches on center.
and they take a 6mm x 1.00mm thread bolt.

i used 1 1/2 inch long bolts to go through spacers to
clear the brake lines attached to the strut tower.
 

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Discussion Starter #13
just finished the avo first initial install yesterday at 3:45 A M .

thought about an all-nighter ,but my semi-good sense won over.
didn't get a chance to take it for a good trial run on the streets.
i'll do that today.

have install pics and will post with flowery narrative..here's one of the finished first initial install .
 

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Discussion Starter #14
i didn't really want to add the two 90 degree angles to the avo return line into the air intake, but the hose kinked no matter what direction i twisted it.

using three times the length of hose eliminated the kinking , but i am hoping a shorter length with the bends will not be a problem .

the stock pcv hose assembly has a number of built in 90 degree angles , so maybe this won't be a issue. we'll see when i run it hard today.
 

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not trying to hijack, but i'm thinking about putting together an oil/air seperator myself. i was wondering in anybody had thoughts about what sort of size i should aim for. can it be too big/small? or should i just make something that will fit where i want it to go?
 

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Discussion Starter #16
I should have finished posting these diagrams ten days ago.
My only excuse is that all I’ve been doing is driving the Sti . 8)

Pic 1 :
This is the 2004 Sti shop manual diagram of what the PCV hose assembly looks like so you can find it in maze of hoses . :eek:

Pic 2 :
I disconnected the factory PCV hose from the PCV End-piece (grey) It has a sensor and wire connected to it and it connects to the intake duct.
To that PCV End-piece (grey) , I connected the AVO outlet hose .
Cleaned-up air from the oil catch can goes into the air intake duct from this hose.
I used two 90 degree elbows to alleviate hose kinking and to keep hose lengths to a minimum.


Pic 3 :
At the end of the disconnected factory PCV hose , that is still connected on the other end to the PCV hose assembly , I used an inline hose connector ( from NAPA auto parts ) and connected the AVO inlet hose to it
Blow-by oil vapors from the engine crankcase go through this hose to be caught and separated in the oil catch can.

pics 2 and 3 are at WOT (wide open throttle)/Heavy engine load. At Light engine load , the air flow directions actually reverse due to negative pressure at the PCV valve.
This is predominately due, of course, to the position of the throttle plate in the throttle chamber .

I used stainless steel hose clamps at all connections

I didn’t connect the rocker cover vents to the catch can ,
so I plugged where a second hose inlet would have been added .

Since this install really uses no Tee’s. it is actually an “ inline “oil catch can installation .
This install should be universal enough to work with any sealed ( not vented ) oil catch can/ oil-air separators available , on stock air intakes .

I haven’t seen any performance degredation in the 2 weeks I have used this install.
I'll report if I catch any oil/sludge/residue in the next few months, and if this initial install really works or not.

Apologies for the LONG posts and MASSIVE byte pics , but these things go Full Mutant on you so quickly .
 

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Discussion Starter #18
the bracket was fabricated from some aluminum scraps i bought at a metal salvage shop .

the Avo unit does have a small right angle bracket welded onto the top with a drilled hole.
i used it to attach to the bracket .
 
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