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ok shake down time for my car tonight... popped cooler pipe but fixed that... then noticed oil everywhere...

the current breather setup:

inlet manifold to breather tap

breather tap to turbo side breather tap

breather tap to catchcan

catchcan to atmo

problem with this so it seems is its pressurising the system and pushing oil to the top of the motor which in turn started forcing oil out of my rocker cover seal thus going everywhere

now our solution is to do it how it is stock... but adding the catchcan in...

current setup stays how it is but the exit from the catchcan going to atmo atm - weld a knoblet on my metal afm/turbo pipe and plumb it back in... so the air is being circulated only problem with that is dodgy afm readings then...

any got any other ideas? pics of your setup maybe?

muchly appreciated,

thanks

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Mine just has two pipes off the things on the cam cover things to the catch can, and then we blocked off the orginal pipes. I then unblocked the orginal pipes as it made a mess of the engine bay with all the vapours going about. That and if its not done correctly it does bugger all anyway.

This is how i done mine,just have the lines coming off the breathers to a catch can, remove the PCV valve (the little valve thats on the intake manifold which the drivers side breather goes into) and insert a short bolt with the exact same size thread (make sure its tight, but dont over tighten, you could even put some thread tape on the thread if you feel the need to), now block off the pipe on the passengers side that goes to the intake pipe (i just used a rubber bung to basically cap the end of the pipe, make sure it dosent leak air, the proper way would be to remove the whole pipe and block off the hole in the intake pipe between the turbo and AFM) works a treat and have never had a problem with it!Pretty simple really

Heres a pic

Picture138.jpg

Picture120.jpg

Edited by nizmo_freek

huddy that is how i had mine... and the exit from catchcan was venting to atmo... question is - was james' too?

anyways weve taken the catchcan out of the equasion and gone stock breather set plumbed back into inlet pipe... see how that goes...

funny thing i have never seen 1 drop of oil in my catch can... so my thoughts was through pipe to top of catch can and sucked straight back up through pipe to intake :S

BUT not 100% on this... and not sure on james V's... only got the pic and cant really tell where that other hose is going :S but cant be too far... must be atmo...

see the catchcan is sposed to take anything in the ventilation out and drops to the bottom of the catchcan and the air goes out the exit... oil generally shouldnt be picked back up (density and stickyness shouldnt allow it unlike say water for instance)

maybe you have no blow-by hudds?

  • 2 weeks later...

Having taken this idea from someone else, when I searched for the same thing some time ago... here is my set up... the hoses that came with it (ones you see) cannot handle the heat under the engine bay.. will change to silicon or similar when I have the inclination. ;) My setup was recommended by SydneyKid, basically it keeps all the pressure of the system like STANDARD, without blocking off pipes... Sound like what you're after... it's a good design, all be it a tad crowded.... but looks "hardcore jap tuner style" IMO :)

ALSO, location of catch can is subject to change... only place mine would fit to some pre drilled holes.

P.S. blue Silicon hose now has taken the place of a lot of those hoses... :) forgive me for the dirty engine bay...

post-19602-1144914873.jpg

Edited by QUIKBLADE
  • 4 weeks later...

Hey guys what's up.

I just had a quick question with regards to catch can setup's.

Well I finally got mine and I want to install it however I'm a little confused on which way to do it. It's like there's two ways of doing it,

1) the way nizmo freek did it by blocking it off at the intake plenum and intake side of the turbo (this is how I'd like to do mine in order to get rid of all the stock crap attached to the turbo side where the maf is)

2) the way QUIKBLADE posted his set up.

So my question is, which way is proper as I've heard it's not good to pressurize the vavle covers? If both hoses run to the catch can, thats what would happen am I correct?

Now I have a 1990 GTS and this is what I considered doing. I was going to block one end of the of the breather on the turbo side. Keep both breathers attached by one hose (across the coilpack cover) and then having both breathers on one hose to the catch can. Then have one hose go from the catch can to the intake plenum on the motor. My thinking for this is that all vapours/oil go from the motor into the catch can and "hopefully" cleaner air with less moisture will go back to the motor. The system is still under normal pressure as it's attached to the engine, right or wrong?

I am probabley making more of this then needs be however, I just don't want to screw anything up.

So any clerification here would be greatly appreciated.

Thanks everyone.

  • 2 weeks later...
So my question is, which way is proper as I've heard it's not good to pressurize the vavle covers? If both hoses run to the catch can, thats what would happen am I correct?

My way is apparently the correct way of hooking up a Catch can setup... basically to not pressurise the system... Although I can still see a stack of oil in the return pipes... ;) Go Figure...

Now I have a 1990 GTS and this is what I considered doing. I was going to block one end of the of the breather on the turbo side. Keep both breathers attached by one hose (across the coilpack cover) and then having both breathers on one hose to the catch can. Then have one hose go from the catch can to the intake plenum on the motor. My thinking for this is that all vapours/oil go from the motor into the catch can and "hopefully" cleaner air with less moisture will go back to the motor. The system is still under normal pressure as it's attached to the engine, right or wrong?

I am probabley making more of this then needs be however, I just don't want to screw anything up.

So any clerification here would be greatly appreciated.

Thanks everyone.

I take it you have a GTS-t as oppose to a GTS which you stated...?... :cheers:

Yeah I had to draw a diagram for myself... but I don't see why that wouldn't work... Basically you have turbo cam breather inlet blocked... and both cam breather "outlets" T'd into 1 hose which will then go to the catch can... then on the other side of the catch can comes a hose to the plenum... yeah sounds, like a solid idea. :cheers: Sorry for a late reply.

i have both cam covers running into a catch can of 1.5L capacity, the return pipe to both the turbo intake and the intake plenum have been blocked off.

i manage to fill the cartch can at a drift prac or comp event, with about 1 l of oil from a whole days thrashing on the limiter.. is this normal or do i have excessive blowby.

I am well aware that RB series engines produce a lot of oil movement in the head at high rpm, some of which will find its way through the breathers.. so is mine normal or excessive?

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