Oil air separator installed but need some pro help here!!!

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Austin2013SHO

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Hey guys I installed an oil air separator yesterday and got it mounted and hooked up but I have a question for my experts out there. So when installing this both lines run from each valve cover and I used the orginal connection there with some AN fittings to get it to fit but the two plugs you no longer use, one on intake manifold where PCV hose ran from back cover to this ****** and the other on the air intake right below where u block off the return for you BOV when venting to atmosphere. Both used these special locking clips before on the original hoses but now I need to cap them off and wanted to know did you find a direct fit block off or did most people just do a rubber cover with hose claps similar to VTA BOV set up. Below I have provided some picks for your to see what I mean. I tried to look at @802SHO set up and seems like he found a plate for intake but I can’t tell for the other. Any love would be appreciated brother.

PS: I mounted this to the back side of my air box and the breathers actually sit right under vents I installed in hood. White spacers were painted purple also.
 

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Austin2013SHO

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Also for now I used original clips connected to old hose, burnt and folded hose inward to make a temporary cap until I find proper one for each spot. You may can see what I mean from pics.
 

802SHO

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Does your catch tank have any internal baffling? What size AN hoses?

You already have the tank setup so if it doesn’t have internal baffling make sure you routinely clean those filters. The filters will saturate in oil vapors long before you fill it up halfway bc the hose inlets are so close to the top where the filters are. It’s essentially a chimney with no internal baffling. Regardless of how full that tank gets you should remove and clean the Filters every 300 miles minimum. Nothing is baffling the vapors except the filters media itself. If you see oil residue or small droplets clean immediately.
A little oil saturation will drastically reduce breathing capacity, even more so if you’re using less than -10AN.

The hose size really needs to be -10 minimum. This is a VTA setup. The bigger the better. I ran into issues with my Racetronix dual 2 liter catch tanks and filters bc the tanks had no baffling. The hoses attached towards the top just like yours. Don’t be like me and not clean the filters. I was assuming they’d get oily….so when they did I checked the tanks ….not much in there at all…plus I would get a visual of vapors exiting. It’s breathing right? Wrong. Under WOT pressures spike instantly. I blew some spark plug seals.

You can make this work as long as you constantly monitor and clean those filters. If your tank does have internal baffling they will stay cleaner much much longer.

You can plug those ports. The air intake side was vent/vacuum source for the recirculating system. No longer needed. Cap and ignore. Make it a good quality cap. Perhaps goggle, 5/8 PTC straight plug. Same for the intake manifold , you’re no longer sending junk back into the valves. I believe all the ports are 5/8 push to connect.

I chose to just redo my whole setup with Motion Raceworks internally baffled catch cans with massive filters. Same one that Cleetus demonstrates sending 2 oz of oil directly into the can with compressed air…nothing came out of the filter, filter remained dry and clean.

I used 2 one for each valve cover. My right rear valve cover is modified, deleting the PCV vapor canister with 1/2 NPT. Everything is -12AN. IMG 7969I don’t have the intake side to bother with on my setup, but for now the intake port is blocked off….its capped with a cap from O’Reillys. It’s getting changed to be the sole source for my fuel pressure regulator as of this weekend. 5/8 PTC 90 to 3/8 barb, then 3/8-1/4 straight barb and 1/4 to the FPR.
 
Last edited:

Austin2013SHO

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Does your catch tank have any internal baffling? What size AN hoses?

You already have the tank setup so if it doesn’t have internal baffling make sure you routinely clean those filters. The filters will saturate in oil vapors long before you fill it up halfway bc the hose inlets are so close to the top where the filters are. It’s essentially a chimney with no internal baffling. Regardless of how full that tank gets you should remove and clean the Filters every 300 miles minimum. Nothing is baffling the vapors except the filters media itself. If you see oil residue or small droplets clean immediately.
A little oil saturation will drastically reduce breathing capacity, even more so if you’re using less than -10AN.

The hose size really needs to be -10 minimum. This is a VTA setup. The bigger the better. I ran into issues with my Racetronix dual 2 liter catch tanks and filters bc the tanks had no baffling. The hoses attached towards the top just like yours. Don’t be like me and not clean the filters. I was assuming they’d get oily….so when they did I checked the tanks ….not much in there at all…plus I would get a visual of vapors exiting. It’s breathing right? Wrong. Under WOT pressures spike instantly. I blew some spark plug seals.

You can make this work as long as you constantly monitor and clean those filters. If your tank does have internal baffling they will stay cleaner much much longer.

You can plug those ports. The air intake side was vent/vacuum source for the recirculating system. No longer needed. Cap and ignore. Make it a good quality cap. Perhaps goggle, 5/8 PTC straight plug. Same for the intake manifold , you’re no longer sending junk back into the valves. I believe all the ports are 5/8 push to connect.

I chose to just redo my whole setup with Motion Raceworks internally baffled catch cans with massive filters. Same one that Cleetus demonstrates sending 2 oz of oil directly into the can with compressed air…nothing came out of the filter, filter remained dry and clean.

I used 2 one for each valve cover. My right rear valve cover is modified, deleting the PCV vapor canister with 1/2 NPT. Everything is -12AN. View attachment 96611I don’t have the intake side to bother with on my setup, but for now the intake port is blocked off….its capped with a cap from O’Reillys. It’s getting changed to be the sole source for my fuel pressure regulator as of this weekend. 5/8 PTC 90 to 3/8 barb, then 3/8-1/4 straight barb and 1/4 to the FPR.
Hey bud thanks for getting back with so much detail I appreciate it. This catch can does have the internal baffling but I will still monitor closely as it’s a newer recently released product, so not sure of its quality yet. Thanks for the tips. Hoses are 12AN I believe, close to 3/4” in diameter.

Thanks for that clarification of what to google I know they make something to just quick connect and plug but couldn’t think of the proper name for it. Push to connect 5/8’s should be right on the money for both of those spots.

Looks good brother. Thanks again.
 

ShatteredMJ

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UPR has quick disconnect block-off caps. They click on and push-to-disconnect just like their catch can lines. The ones you pointed to are all 5/8. I don’t believe UPR lists them on their website, but just reach out to sales and they will make you an invoice for whatever you want.

[email protected]
 

802SHO

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Hey bud thanks for getting back with so much detail I appreciate it. This catch can does have the internal baffling but I will still monitor closely as it’s a newer recently released product, so not sure of its quality yet. Thanks for the tips. Hoses are 12AN I believe, close to 3/4” in diameter.

Thanks for that clarification of what to google I know they make something to just quick connect and plug but couldn’t think of the proper name for it. Push to connect 5/8’s should be right on the money for both of those spots.

Looks good brother. Thanks again.
3/4 OD is -8AN territory. That’s why I asked. They looked like -8AN to me.
 

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