catch can

gtlegacy · Post by **gtlegacy** » Sun Feb 24, 2008 1:46 am

Heya,

i am thinking about hand fabricating a catch tank for my legacy gt 1990 gt ej20g

now my question is wat the crap is that in my picture its attached to the intake and goes to that black boxy thing on the intake piping before the turbo ?

i plan to route the head vents from left and right hand sides of the engine to one inlet and if the thing in the picture is meant to connect up somewhere there to a 2nd inlet then just make a new pipe and attach 1 outlet to that pipe on the intake

and then make a smaller 2nd can for the the crank case breather and go between the join and the throttle body inlet

i plan to fill them with a air filter element material foam
and basically have one side for the inlet with the foam and then the other side for the free air to leave

can somebody advise to whats that in my picture and its function

and also if you think my idea for catch can is good ?

the only reason i dnt want to buy new is id rather just build it !!!!!

its fun !!!

go here for pics and check out my other pics of my legacy lol

vrg3 · Post by **vrg3** » Sun Feb 24, 2008 2:18 am

That's a picture of the Idle Air Control valve. The IAC valve is used to let air into the intake manifold around the throttle plate.

gtlegacy · Post by **gtlegacy** » Sun Feb 24, 2008 3:25 am

ok so can i make an inlet in my catch can for that or do i just direct that into the intake the standard way through the black box before turbo ?

vrg3 · Post by **vrg3** » Sun Feb 24, 2008 8:35 am

I wouldn't involve the IAC stuff with a catch can.

gtlegacy · Post by **gtlegacy** » Sun Feb 24, 2008 8:43 am

ok sweet az ill probably just make a larger and a small can and do it the way i said without the IAC valve

gtlegacy · Post by **gtlegacy** » Sat Mar 15, 2008 2:03 am

ok im at the stage where i want to make my cans ?
i have a td05h 16g at 14psi in an ej20g

i plan on running a in from side 90* to bottom and a breather filter on top with sum mesh or sumthng inside

1 What pipe diameter would be optimal in my case the standards have 16mm inside diameter this is the 2 from the heads and 1 from crankcase linking with LH head ( i can modify the breather fitting on the head )

2 Will making catch cans upset the pcv ? how will i route this into the set up ?
do i need 2? if not wat do i do with it ?
the pcv is under the throttle body on intake manifold right?

3 is this the usual way the lines are routed ?

also i need some help on the intake side of things the the IAC

I have an hks recirc bov so im going to make a new bit of pping where the black box goes to flow the waste air back into the intake

where should the IAC pipe be added into the equation ? it will have to be somewhere in the new pipe it will be the same length and diameter as the black box

do i need to add it in at all ?

Canadian Turbo · Post by **Canadian Turbo** » Sat Mar 15, 2008 3:26 am

Ya, nice car man. Funny I already had picture of your car on my desktop, weird.

gtlegacy · Post by **gtlegacy** » Sat Mar 15, 2008 3:53 am

SubaruNation · Post by **SubaruNation** » Sat Mar 15, 2008 3:56 am

Canadian Turbo wrote:Ya, nice car man. Funny I already had picture of your car on my desktop, weird.

gtlegacy · Post by **gtlegacy** » Sat Mar 15, 2008 3:58 am

ok and what does that have to do with my catch cans

SubaruNation · Post by **SubaruNation** » Sat Mar 15, 2008 4:02 am

vrg3 wrote:I wouldn't involve the IAC stuff with a catch can.

check it.

this is the word of god. ya read it and appreciate it

gtlegacy · Post by **gtlegacy** » Sat Mar 15, 2008 4:07 am

oh yea sorry i should of been a bit clearer on tht 1 i am making a new part the intake where that big black box is im nt connecting the catch cans to the intake itself only in the throttle body pcv area

the IAC stuff i wanted to knw if i have to have that connected and whyat driection it needed to face to my new fabricated part in place of the box as i have a different bov recirc and i wanted to remove the box

how does it work ? does it release air from the intake mani for does it pick up air pressure from the box and controls idle that way ???

gtlegacy · Post by **gtlegacy** » Mon Mar 17, 2008 5:19 am

can somebody reply to the above the 6th post

93forestpearl · Post by **93forestpearl** » Wed Mar 19, 2008 6:29 pm

I was running a catch can. Then one day I was driving (2 degrees outside) and my car started to seriously smoke from under the hood and out the exhaust. What happened was the fittings on my catch can iced up and so did my pcv valve and I was building pressure in the crankcase. Pressurized crankcase means the turbo can't drain and it puked a quart of oil between both sides of the turbo. Needless to say I wan't happy about the situtation. It took lots of brake and carb cleaner to take care of that mess.

Just be careful in the winter (if you get that kind of climate) as journal bearing turbos don't take well to that kind abuse.

gtlegacy · Post by **gtlegacy** » Wed Mar 19, 2008 7:39 pm

sweet ill keep that in mind

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catch can

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