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-   -   Must read!! oil catch cans and AOS's!!!! (

synolimit 05-26-2010 11:15 PM

Must read!! oil catch cans and AOS's!!!!
So I have 13k miles on my car. I had my crank case catch can on for almost a month and look what I got! Now 90% of this is water and the rest is oil gunk, but itís a lot and my motor is thanking me for not letting it get down into the motor!! My advice is no matter what parts your running, a catch can for the crank case and valve cover vents I believe is a must!! If all this is just from the CC, imagine double is coming from both of your valve covers getting into your motor!

Well tonight I pulled all the VC hoses off and there was oil and stuff in them too. So I got more hose and now venting the CC and VC together to my catch can. Like I said before I only have 13k miles on my car, I DO NOT drive in boost all the time or drive hard on the street. I just get up and go from point A to point B like a normal person. Sometimes on the highway here and there, but the point is if im getting this much, then you are probably getting worse!! Your motor isnít gonna like you with so much oil and water getting down into it.

On a side note!!!! You may not get as much if you do a catch can from your CC. WHY? I have a blow though set up so I took off my PCV valve. Your stock system runs a hose from your CC to a T. The T then runs to your PCV, then to your intake manifold. The other side of the T runs to your inlet. My set up is running 100% CC crap to my catch can while other people are only running 50% (the other 50% is going to their PCV valve where it is then running to their intake manifold and into there motor=bad!!). I think everyone should look into a catch can or AOS separator no matter what your set up may be!!



RcrsWetDream 05-26-2010 11:30 PM

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Agreed..... Low priority on my list but still something I need to do... Probably go with the grimmspeed aos since I'll need to run 2 or 3 catch cans for the same result... I just want to do my research on the aos to make sure it's not dropping water into the oil before I go that route.

pzr2874 05-27-2010 05:54 AM

Chris, look at IXIZ Concept's AOS.... Ming did a great job on his.

WReXd 05-27-2010 01:22 PM

Take a look at the SGMotorsports AOS, same style as Grimmspeed and Prova. There's a group buy going on for it right now.

fuapiti 05-27-2010 01:47 PM

Can you post a picture of your engine bay to see where you t-ed off to install your OCC?

Zaridar 10-17-2012 07:31 PM

letting ambient air get into your crankcase (via crank vents) will probably increase the amount of moisture in there...

synolimit 10-17-2012 08:19 PM

with the engine running the pressure should be positive if only slightly (at idle) so air getting in isnt a problem. this is confirmed by oil analysis showing perfect numbers (no high water levels, in fact showing 0.0 h2o).

thelastleg05 04-17-2013 08:29 AM

Hey I just want to say thanks for your great catch can post and info. It has helped me greatly with deciding what to do. I already have bought most of the parts to make my own (copyed yours). Just need stainless steel wool, and did you reduce the 3/4 CC nipple to 1/2 before it entered your can?? I just could not find that info but read the whole 16ish pages. (I was glued to that thread, the GF was not pleased with me haha)
Good Info!!

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