Oil Catch Can Diagrams

[kasalem_86]

Hi Everyone,
I am working on getting everything ready for my blow through conversion on my 2002 gt vortech v1. When I looked into breather tanks / oil catch can setups I noticed there are several ways people are connecting them, so i went and made a picture three different ways not knowing which one would be best. I called JAZ, UPR, and American Muscle and they all said to go with #2. Another member 'mineralgrey02k' has his set up the same way as well.

For some reason #1 makes the most sense to me , but i see what you think.

(I will be using the JAZ mini breather tank as a catch can)

 

[kasalem_86]

Here is a link to JAZ's webpage , second product on the page

..:: JAZ PRODUCTS ::..

The can's barb fittings are 3/8's in size, i measured 5/8" on the valve cover's driver's side, passenger side, and plenum.

The 5/8" hose that came with my vortech kit is a thick heater hose. People recommend using an oil resistant hydraulic hose, due to having heater hoses collapsing under boost . although I have no experience as how flexible the hydraulic hoses are to bend.

 

[TBapp3]

Wish I could help out but it sounds like a mean project !

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[kasalem_86]

Thanks , yeah not to many have tried the first setup on the mod motor

 

[cobra20sc]

The function of these setups are typically to separate any oil in the air being vented out of the valve covers from crankcase pressure in both idle and full boost conditions. Closed looped systems are typically best so as not confuse the computer with the loss of metered air. But depending on driveability/tunability/etc. it may be acceptable to vent the air through a breather. Your call on that but to me, it makes most sense to account for all air that has passed through the MAF. That being said:
1) This setup won't work, it will only allow relief of crank case pressure under idle conditions. The vacuum in the intake manifold will help pull the pressure out of the valve covers. The separator/catch can will filter any oil. However, under WOT conditions, the intake will ALWAYS be at a higher pressure than the valve covers. I'm assuming you'll have PCV check valve at the valve covers so there essentially will be no flow and no release of crank case pressure that typically occurs during boost conditions.
2) This setup will work. You'll have the left side working as in setup #1 above. But you will also have unmetered air released to atmosphere through the breather during idle AND WOT conditions.
3) This setup will work as well same as #2.
I'm not sure there's anyway to run a fully closed system on this blowthrough type setup since the MAF is in a pressurized region. Plenty of people running breathers so it must be ok. I'd got 3 because 2 can get messy.

-Chris

 

[kasalem_86]

Great Response Chris. Thanks for your input. That makes alot more sense to me on how the system operates now...

I also wanted to know if running a similar setup to #2 , without a breather on the driver's side cover. Instead running a hose with a "T-fitting" to the catch can inlet sharing it with the passenger side hose?
only for the sake of not having two catch cans.

I am working on two more drawings , this time having one side of the catch can venting back into the pre-maf part , after the intercooler.

 

[kasalem_86]

Here are two more attached in the photo file.

I hope one of these works without messing with the metered air .

Thanks

(notice the unintentionally penis-shaped powerpipe) :nono:

 

[cobra20sc]

Great Response Chris. Thanks for your input. That makes alot more sense to me on how the system operates now...

I also wanted to know if running a similar setup to #2 , without a breather on the driver's side cover. Instead running a hose with a "T-fitting" to the catch can inlet sharing it with the passenger side hose?
only for the sake of not having two catch cans.

I am working on two more drawings , this time having one side of the catch can venting back into the pre-maf part , after the intercooler.

I had an issue opening the pic so I couldn't see anything much more than the thumbnail. Your first suggestion I think just puts you back to option 1 in your original post. Second option won't work because any point downstream of the compressor, (like after the intercooler) will be pressurized and therefore will not let any crankcase pressure flow into it. Plus if you're looking to keep it closed(no unmetered air) you need to introduce the air downstream of the maf. Again, I'm not sure you can get to a closed setup on a blowthrough setup like this. Since its only the case of wot situations, probably can just be tuned out with less wot fuel multiplier to counter any richened condition.

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