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make sure you keep the restrictor in the breather hoses, it is there for a reason

Do all RB engines have that or just 26's? When I setup my breather system I looked for a restrictor in the stock breather hoses and there was nothing...

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Do all RB engines have that or just 26's? When I setup my breather system I looked for a restrictor in the stock breather hoses and there was nothing...

As far as i know its only the 26 that has that on there, i know my 20 doesn't and i'm fairly confident the 25 doesn't either.

I highly suggest you read this, as it has pretty much all the answers to your questions thumbsup.gif

http://www.skylinesaustralia.com/forums/topic/314402-project-rb31dett-the-development-of-my-open-deck-rb-engine-and-the-quest-for-more-torque/page__view__findpost__p__6039475

Will this be efficient?

*excluding the breather though.

IMG_0196.jpg

No!. All this is doing is blowing the exh side gasses straight back to the turbo intake, totally defeating the purpose of installing the catch can - more correctly "oil-air-separator".

Leave the "U" hose connecting the 2 rocker covers. Disconnect the hose going from the exh cover down to the intake side of the turbo, and re-direct that to the catch can. Run the other fitting on the catch can back to the inlet side of the turbo. Simple.

Edited by blind_elk

Do all RB engines have that or just 26's? When I setup my breather system I looked for a restrictor in the stock breather hoses and there was nothing...

My 20 had a brass restrictor in the return pipe to the intake for the factory breather setup

No!. All this is doing is blowing the exh side gasses straight back to the turbo intake, totally defeating the purpose of installing the catch can - more correctly "oil-air-separator".

Leave the "U" hose connecting the 2 rocker covers. Disconnect the hose going from the exh cover down to the intake side of the turbo, and re-direct that to the catch can. Run the other fitting on the catch can back to the inlet side of the turbo. Simple.

Thanks alot man. That's all I wanted to know haha.

On my old gtr I had the autech style oil/air separator that sits ontop of the cam covers,

My new gtr has the pcv blocked, oil return to turbo inlet blocked and just running 2 hoses from cam covers to an atmo catch can, anything wrong with this besides been illegal?

Not a huge fan of this setup but that catch can/washer bottle fills the spot where the battery was (battery is relocated to boot)

The advantage of having the catch can breather connected to an intake is that it creates suction and helps clear the vapours better. This requires a proper catch can which functions as an oil/air seperator or a seperate oil /air seperator (you don't have to buy the Nismo ones - Moroso do them cheaper or you could have one fabricated) in the line. If you are having a catch can made you can specify proper baffling. Some catch cans have removable tops and bottoms and you can check and modify them yourself if necessary. Some ebay catch cans are so small and useless as to be for show only.

If you have heaps of blow by for what ever reason and the catch can set up you have is not coping then you will not want to feed this into your intake. Preferably you will fix the problem or modify your system to deal with it but (in NZ anyway) you can vent to atmosphere for track cars.

I have seen the engine bays of a number of Japanese race cars that have air oil seperators and one or two catch cans and run the breathers into the intake.

Indeed the good old steel wool in a stocking will be going inside the can.

This does f**k all, trust me. It's more likely to leave you with bits of disintegrated stocking and metal fibers in your intake then separate any oil from the air.

You have a GTR, give it the parts it deserves and get a properly baffled catch can. I got my custom combined 2L catch can/radiator overflow bottle from Pro Fabrications for $390 delivered, Brad is a good bloke and knows exactly what he is doing. Spend a bit more cash and do it right.

426487_10150508799027541_519882540_9106071_909800602_n.jpg

Edited by Hanaldo

i have a catch tank just like the one above n seems to work well.

i have a drain hole at the bottom of the can and i also have a spare fitting on the bottom of my extended sump.

if i was to run a braided line from the can directly to the sump would this be effective? or will oil from my sump just run up that line back towards the can?

When we do a sump & catch can for the same vehicle I always suggest a breather hose from a high point of the sump above oil level to the base of the catch can.

It just provides a better vent for the crankcase not a drain for the catch can.

This does f**k all, trust me. It's more likely to leave you with bits of disintegrated stocking and metal fibers in your intake then separate any oil from the air.

You have a GTR, give it the parts it deserves and get a properly baffled catch can. I got my custom combined 2L catch can/radiator overflow bottle from Pro Fabrications for $390 delivered, Brad is a good bloke and knows exactly what he is doing. Spend a bit more cash and do it right.

I was waiting for this quote. Obviously Im looking for my best option. Not OH MY GOD NIIIIISSSSSMMMMOOOOOOO! haha.

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