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Rb20Det - Oil In Intake

argh32
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argh32 Contributor

argh32

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Hey guys and girls

Hopefully someone can give me a little more guidance here. I have an r32 rb20det track car that I take to Queensland Raceway to drift etc etc..

Basically what happened - I was giving the car a pretty good boot full on the track and came in to cool down a bit. I noticed that there was a little bit of oil coming out of a split in an intake hose onto the tappet covers. When I was driving it I didn't notice any difference in performance or feel. I pulled off the crossover pipe and it had oil in it. I did a compression test with 140-148 results. I installed a catch can today and when I took it for a drive I couldn't get my turbo to reach above 7-8psi. It is usually at about 12psi. There is also a little bit of noise coming from the turbo area.

Turbo seals?

Turbo is no good?

I know I cant really get an accurate diagnosis over a forum, but if anyone can give me some advice it would be much appreciated.

Is my catch can setup going to do its job?

Cheers :)

post-97480-0-87756900-1368691490_thumb.jpg

post-97480-0-81826900-1368691497_thumb.jpg

Edited by argh32
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blind_elk Grand Master

blind_elk

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Are you sure you couldn't have done a more complex job on the plumbing?

The simple solution is to simply run a line from the ex rocker cover to the catch can, and another line from the catch can up to the turbo inlet. Everything else remains as per factory.

It might then solve your (lack of) boost problem.

Dan_J Veteran

Dan_J

Posted
Posted

if its a track only car and defects ain't a problem, just block intake pipe and pvc valve then run a line from the rocker covers to catch can and put a mini breather on the can..... set up wont work with out a breather.

also if you have an air leak on the intake pipe you can lean out and kill the engine as afm cant read the extra air

argh32 Contributor

argh32

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But if I only run one line from either the passenger or drivers side cover, won't the other side still be able to put oil into the intake?

If I block that one to stop that will it give the motor less room to breathe under higher RPM?
Like this - http://www.skylinesaustralia.com/forums/index.php?app=core&module=attach&section=attach&attach_rel_module=post&attach_id=220638

That was my train of thought on the catch can situation anyway.

Edited by argh32
argh32 Contributor

argh32

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  • Author
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if its a track only car and defects ain't a problem, just block intake pipe and pvc valve then run a line from the rocker covers to catch can and put a mini breather on the can..... set up wont work with out a breather.

also if you have an air leak on the intake pipe you can lean out and kill the engine as afm cant read the extra air

Is the PVC valve the inlet on the plenum that I have my red hose on? Sorry for the nub question

Dan_J Veteran

Dan_J

Posted
Posted (edited)

^its the valve that's bolted onto the intake plenum

in that picture the intake pipe is still connected. i mean block the line on the pvc valve and the one on the turbo. then put a lil air breather on the catch can and connect up the rocker breather line to the catch can

e911cf73-4186-4004-a775-5511e53b846b_zps

but wont work with out this ^^^

Edited by Dan_J
blind_elk Grand Master

blind_elk

Posted
Posted

But if I only run one line from either the passenger or drivers side cover, won't the other side still be able to put oil into the intake?

No. What you are effectively doing is inserting a catch can into the little hose that runs from the ex rocker to the turbo. The can - more technically "oil-air separator" - will condense out the oil vapour (particularly if you fill the can with some steel wool). The in and ex covers are still connect by the "U" hose.

It's PCV - Positive Crankcase Ventilation (PVC is PolyVinylChloride). It only opens under high vacuum (basically @idle), and ingesting a bit of oil vapour at less than atmospheric is not adverse for the engine.

argh32 Contributor

argh32

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Ok yep, that makes sense to me now.

This morning I blocked off both the PCV inlet and the turbo inlet and my turbo still stayed at about 8psi max.

What should my next move be? Could it just be a lose connection in the intake that I cant find? Would I usually be able to hear the vacuum from a leak?

Dan_J Veteran

Dan_J

Posted
Posted

No. What you are effectively doing is inserting a catch can into the little hose that runs from the ex rocker to the turbo. The can - more technically "oil-air separator" - will condense out the oil vapour (particularly if you fill the can with some steel wool). The in and ex covers are still connect by the "U" hose.

It's PCV - Positive Crankcase Ventilation (PVC is PolyVinylChloride). It only opens under high vacuum (basically @idle), and ingesting a bit of oil vapour at less than atmospheric is not adverse for the engine.

i ALWAYS get it mixed up but, 'yo peeps know what i'm on about' :P

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