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-   -   new oil catch can setup (

synolimit 10-22-2010 12:28 PM

new oil catch can setup
Well I was bored today. Also I was tired of my old oil catch can set up. I had a Greddy catch can that could over flow into a TurboXS modified coolant overflow bottle. Since both were metal however they condensated like a mother fíer! I was having to take them off and drain them every 1500 miles. Along with being metal they sit right in the path of cold air from the hood scoop. Two things that donít go together well when trying to battle condensation. They were also a pain because the barb fittings really grab onto the hose and you cant pull them off!!

So new setup began. First I didnít want to pull hoses off anymore so I decided to drill a hole in the bottle of my new catch can for a drain hole. Yes I could have done this with the two other cans but I want to avoid metal. My hoses also had to be reduced in the old setup. The crank case line and the valve cover lines are around 1/2in. The Greddy can was a lot smaller so I had a bunch of brass fittings making the reduction because I could not find the right reducer in one piece. Problem solved as I made the new fittings 1/2in.

Next thing I wanted was SIZE!! The two old cans were very very small. Pain in the butt to always drain because of their size. So 4Ē pipe by 13in is plenty big enough! In all I spent $35 for 2 foot of PVC pipe, 2 rubber end caps, 2 worm clamps, 2 1/2in fittings, and a T bracket; I had everything else. The top of the T bracket is clamped to the pipe and the bottom of the T bracket is bolted down to an existing bolt holding the AC lines.

All in all I think it will work nice. Its plastic now and not metal. Its large and not small. And it will be easy to drain and work on.

A few more things I wanted to add. My car as been running this way for almost 10k. theres been no problems with the crank case and the valve covers going to the same can. Every 1500 miles I was only getting about 2 table spoons of actual blow by. You know the Yellow nasty looking crap. The valve covers crap is more black burn oil liquid stuff. The Yellow crap was all from the crank case. I have done 3 oil analyses by the way and all were well above the norm! Engine is extremely happy and clean. I also donít have the catch can going back to the inlet tube because my MAF sensor being blow thru was getting dirty. Some crap was obviously getting out of the catch can and back into the system. So now its just vented to the atmosphere. Neither the old setup or the new setup had any type of media in the cans. Thatís why some was still getting back out. I havnt done it yet but I do plan on putting steel wool in the can to help hold the blow by in and not have it and the water slosh around so much. And of course ill paint it!





brfatal 10-23-2010 01:29 AM

So, you know our cars run a closed loop oiling system right? Why the vent?

synolimit 10-23-2010 09:05 AM


the stock system runs everything back in to the manifold (PCV) and inlet from the CC and the valves run it to the inlet. caping them off would be a pretty bad idea if i had to say so. the crank would build pressure from the blow by. without escape the oil pan would want to blow. never cap them off

subyaddict 05-07-2011 11:48 PM

Is this setup still working well for you? I'm about to put a new turbo inlet on and I'd like to put a catch can on at the same time. I like the way you did this. It looks clean, especially if it was painted.

synolimit 05-08-2011 12:04 AM

sure is! i get just a very very small amount of yellow blow by and a lot less water from condensation. at 3000 miles when i change my oil, if i had to guess about 6-8 onces of water comes out. only downside is running steel wool because it rusts. i need to find stainless steel wool.

[quote=subyaddict;260874] It looks clean, especially if it was painted.[/quote]

of course i did!


FYI if you use steel wool i wouldnt run it back into the inlet like stock. when the steel wool breaks down peices could break off and get sucked into your turbo and motor.

BLAZE2099 05-08-2011 12:08 AM

couldn't you just filter it? ya know, to stay away from that possibility.......for now, until you find another route ...stainless?

synolimit 05-08-2011 12:19 AM

if your making your own why run it back at all like stock? its not needed so just cap off the inlet return nipples and vent to atmos.

subyaddict 05-23-2011 12:02 PM

Did you keep the pcv valve or delete it? I've seen some VTA catch can set ups with the pcv valve deleted.

synolimit 05-23-2011 04:06 PM

i first deleted it because im blow through and perrin said you needed to. my tuner said either way would work. i dont know, i feel better deleting everything to the manifold and inlet so im only dealing with 100% pure air. im currently debating deleting the EVAP system- the hose to the inlet, 2 solenoids on the manifold and possibly whats in the trunk.

subyaddict 05-24-2011 10:26 AM

I picked up all the stuff to make mine the other day. I will post pics when I'm done. Thanks.

thelastleg05 04-17-2013 08:37 AM

Just want to say great help. Will do that same on the LGT. Just curious did you reduce the 3/4 CCV to 1/2 before you went into the can. I assume so since you have 2 1/2 barb fittings. Thanks!!

thelastleg05 04-24-2013 08:42 AM

Scott, Not to try and re-birth an old thread, but I just finally had time to hook up my catch can like i saw yours routed. I have deleted my pcv and ran a straigt hose to the can, then teed the valve cover lines and routed them in the can. I have an atmospheric vent. but when i started it up massive white smoke came out... Is the 05 lgt different than your wrx set up, or did i over look something?

synolimit 04-27-2013 01:58 PM

I did reduce the hose, not sure of the size but they are like one size smaller.

No its the same. If everything was done right (sounds so) there should be no issues. Was the manifold pcv port capped off and stuff? Add pics

BLAZE2099 04-27-2013 07:48 PM

Yeah, I'm doing this in the near future, may get a bit creative on the can though, not too sure. But I like it more than the aftermarkets

thelastleg05 04-30-2013 05:39 PM

So here is the story.
When i first started my car i had both pcv, and crank case vaccum going to atmosphere. My car ran incredibly rough and i could hear a vacuum leak. I could not find the leak so i went the route of hooking up the catch can, wondering if that was the noise. Nope it wasn't and then my car started blowing mass amounts of white smoke out of the dp. At first i thought my fuel pump shorted out because i still have the opening exposed for the checking after i fill my tank up (after installing a dw65c) but it wasnt. So then I thought hmmm must be a catch can issue, and S*&t did i blow my head gasket by doing this.... Well fixed the vacuum leak, and by then i made 2 separate cans (made no difference). started the car last night ran and idled great except after about a min white smoke again. So ripped out the newly rebuilt turbo and found the housing is cracked!! Ohhh darn, now the housing is at work, and we are going to try and weld it, if that does not work, just going to eliminate coolant and buy a turbo timer. So that's my story yee haw

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