Any opinions on this subject?

I've straight pipes run to this kind of can:

http://www.ebay.com/itm/OIL-BREATHER-TANK-CATCH-CAN-3-8-NPT-AN6-AN8-AN10-STAINLESS-FILTER-/140997017324'> http://www.ebay.com/itm/OIL-BREATHER-TANK-CATCH-CAN-3-8-NPT-AN6-AN8-AN10-STAINLESS-FILTER-/140997017324

My system only runs to atmosphere! I've put filters on the end of both braided lines near my air filter to suck up any oily smells! ;-)

The issue you have is with venting to atmosphere you have to run larger breather hoses to account for the fact that when it's put back into the inlet the turbo vacuum is sucking the breather system

So take that away to stop any crank pressure you need to vent it faster

Speaking to a top engine builder they say you would need to run 25mm breather hoses to get crank pressure to 0

If you run to small you will create high crank pressures and cause more wear and oil usage in the bottom end

Found this informative video about catch cans and ventilation.

 

https://www.youtube.com/watch?v=Zo4SltHUGd4

 

Excess moisture buildup explains my oil sludge problem, had 3 feet long cranckcase to catch can hose completely full of it 

interesting as i have thought about this

 

I looked at this guide

 

http://www.audi-sport.net/vb/a3-s3-forum-8l-chassis/118021-guide-how-fit-catch-can-simplify-pcv-system.html

 

where the guy is venting to atmosphere taking hose to back of car.

 

Uses same OCC as I have.

 

But reading the various threads and comments as  the block needs a recirculating closed system to help vent the crank pressure using the PCV , the removing the PCV and venting to atmosphere seem a bit iffy...

You can but you need to use bigger hoses to allow the flow out to atmosphere without the help of vacuum

Think Jp from jbl said 25mm hoses would be needed to get the crank pressure to 0

I'm using 1 of these

 

 

But as you can see from this pic, they have a pretty wide vent:

 

I'm using 1 of these

got any pics of that plumbed in ?

got any pics of that plumbed in ?

No but will try and take 1 tomorrow if it's not raining.

I'm using 1 of these

 

 

But as you can see from this pic, they have a pretty wide vent:

 

 

I take it though you have the PCV still plumbed in and it is just the catch can that vents?

 

Or is  one of those hose's not connected anywhere?

 

I think what Clive meant was if ditching the PCV a larger hose (around 25mm) is needed from the catch can output, to take vapor and pressure out quick enough.

I take it though you have the PCV still plumbed in and it is just the catch can that vents?

 

Or is  one of those hose's not connected anywhere?

 

I think what Clive meant was if ditching the PCV a larger hose (around 25mm) is need from the catch can output, to take vapor and pressure out quick enough.

PCV is long gone mate

got any pics of that plumbed in ?

 

Not the cleanest of engine bay's but it's there to do a job, not to look pretty (thats my excuse anyway )

 

 

 

 

 

 

 

And blanked off where the pcv (hocky puck) was.

 

PCV is long gone mate

 

 

 

Not the cleanest of engine bay's but it's there to do a job, not to look pretty (thats my excuse anyway )

 

 

 

 

 

 

 

And blanked off where the pcv (hocky puck) was.

 

 

So i take it your crankcase hose connects to the other side of the catch can. So you effectively still have a close loop system with the catch can venting directly.

 

As my catch can is the SAIKOU MICHI one without venting breather i typically would end up with a closed loop and maybe have it like the install guide posted above.

 

That set up does not seem as good as yours.. as your would tend not to pull more oil in the can as it is passing back into the head like my current set up.

 

hmm ...... 

 

 

So i take it your crankcase hose connects to the other side of the catch can. So you effectively still have a close loop system with the catch can venting directly.

 

As my catch can is the SAIKOU MICHI one without venting breather i typically would end up with a closed loop and maybe have it like the install guide posted above.

 

That set up does not seem as good as yours.. as your would tend not to pull more oil in the can as it is passing back into the head like my current set up.

 

hmm ...... 

 

Correct, rocker cover to OCC and then crankcase to OCC (from the stupid plastic 90° bend that snaps as soon as you look at it), and the OCC vents direct.

 

I collect very little in the OCC with it connected like this, infact the only time i've had it breath heavily was at Combe last September as I over filled it with oil by about 1/4 a litre (long story) but basicly it spat out the 1/4 litre it didn't want and hasn't breathed anything out since (or atleast so little it's not noticeable), I guess because the PCV is no longer in use, there is no vacumn to pull oil out of the engine, it will simply breath when it wants / needs to.

looks a very neat and well thoughout setup

Correct, rocker cover to OCC and then crankcase to OCC (from the stupid plastic 90° bend that snaps as soon as you look at it), and the OCC vents direct.

 

I collect very little in the OCC with it connected like this, infact the only time i've had it breath heavily was at Combe last September as I over filled it with oil by about 1/4 a litre (long story) but basicly it spat out the 1/4 litre it didn't want and hasn't breathed anything out since (or atleast so little it's not noticeable), I guess because the PCV is no longer in use, there is no vacumn to pull oil out of the engine, it will simply breath when it wants / needs to.

 

cheers  that explains it well.

 

Yeah that stupid 90' bend snapped when i tried to remove mine and i just managed to collect the pieces before they dropped in to sump.

 

good simple job you did there...

 

Is it a baffled catch can?

 

where did you get it if you don't mind me asking..

 

I may sell my SAIKOU jobbie 

cheers  that explains it well.

 

Yeah that stupid 90' bend snapped when i tried to remove mine and i just managed to collect the pieces before they dropped in to sump.

 

good simple job you did there...

 

Is it a baffled catch can?

 

where did you get it if you don't mind me asking..

 

I may sell my SAIKOU jobbie 

 

Cheers, the can is not baffled that I can see, but because the vent is at the top of the can, I don't think it would need to be as heavy oil will drop to the bottom and the "mist" will vent straight out, it can't go back into the engine unless it goes back the way it came, which isn't a problem anyway.

 

I bought it from a friend that had it kicking around in his box of bits, it's a 2.0T FSI kit, but it doesn't look like BSH sell it anymore.

 

It was this kit: http://pgperformance.com/bsh-fsi-race-catch-can.html

I may sell my SAIKOU jobbie

are you thinking the catch can setup affects how much oil goes through/gets caught by the system ?

 

 

It was this kit: http://pgperformance.com/bsh-fsi-race-catch-can.html

 

 

To avoid allowing the scent of PCV gasses from entering the cabin you will want to use the recirc feature on your air conditioning.

:eek:

The only time i've smelt anything inside the car was when I over filled it with oil and it spat the excess out.

 

I've never smelt it before or since then.

are you thinking the catch can setup affects how much oil goes through/gets caught by the system ?

 

No not really , but the link i attached earlier , (this one http://www.audi-spor...pcv-system.html) shows the SAIKOU like mine (no breather filter) the guy was using and venting to atmosphere from the output pipe rather than a closed recirc. Somewhere I read that with a none closed recirc system you get :

- much more fumes

- more oil in can as it is not being re circulated back(although even in a closed recirc the oil will lend up in inlet / turbo hose albeit very small amounts)  

 

To avoid allowing the scent of PCV gasses from entering the cabin you will want to use the recirc feature on your air conditioning.

 

:eek:

 

lol yeah i read that on their site...

 

I an not bothered too much about that but i think my PCV is playing up and rather than replace it I was thinking of your set up is better and you are still using a closed loop and not venting from a outlet pipe.

Mind you i can't seem to find a OCC that has the large breather and 19mm connections:(