Crank Case Venting

[Bo White]

I run Elite Engineering on both sides.

[Badbubba]

Originally Posted by RupertPupkin

Nothing is connected on the clean side.

Then there's really no need for a catch can. You could just vent to atmosphere. At high rpm, there is very little manifold vacuum. So any crankcase pressure would vent through the MM breather. At low rpm, the manifold has a lot of vacuum. But there is no clean air supplied to the crankcase. So you are not having the benefit of removing the contaminated vapors. Besides, as I mentioned earlier, the intake manifold is pulling from both the breather and crankcase. So unless there is some crankcase pressure at low rpm to push crankcase vapors into the can, the manifold will only be pulling air through the breather. As long as the breather is open to air and does not have a check valve, as someone stated that is the case in an earlier post.

[Badbubba]

Ok, found this on MM website, Google Docs. So this changes some of my previous statements. It appears the breather does have a check valve. Not to allow outside air in the breather, but only vent when there is pressure. Which makes sense. What doesn't make sense, is why you would have excessive crankcase pressure, as it would vent through the breather. Possibly pressure isn't the reason the seal failed. It could have been defective or damaged when installed. Most of the time, from what I've seen and read, the rear seal leaks due to pressure. That's where mine was slightly leaking. You could test the can as stated in the pic. I would also add a clean air feed with it's own catch can.

[RupertPupkin]

Originally Posted by Badbubba

Ok, found this on MM website, Google Docs. So this changes some of my previous statements. It appears the breather does have a check valve. Not to allow outside air in the breather, but only vent when there is pressure. Which makes sense. What doesn't make sense, is why you would have excessive crankcase pressure, as it would vent through the breather. Possibly pressure isn't the reason the seal failed. It could have been defective or damaged when installed. Most of the time, from what I've seen and read, the rear seal leaks due to pressure. That's where mine was slightly leaking. You could test the can as stated in the pic. I would also add a clean air feed with it's own catch can.

That is the million dollar question. I would row through gears as much as possible, and hit boost a lot also. Only thing changed was the tune. Only thing I can do now is prevention. With that being said, I think my awesome drawing is my plan of attack. I would add a vented catch can from the clean side to my ECS, but there’s no port to attach to. So I would just add a breather. Should I add a breather on the passenger side valve cover? I saw another forum member here that did it.

[Badbubba]

Originally Posted by RupertPupkin

That is the million dollar question. I would row through gears as much as possible, and hit boost a lot also. Only thing changed was the tune. Only thing I can do now is prevention. With that being said, I think my awesome drawing is my plan of attack. I would add a vented catch can from the clean side to my ECS, but there’s no port to attach to. So I would just add a breather. Should I add a breather on the passenger side valve cover? I saw another forum member here that did it.

1st I would test the catch can for proper operation. The connections on yours are different than the one I posted from their website. The small clear plug, guessing site glass, is below the fitting that goes to the intake side of the tb. Your clear plug is below the fitting that comes from the oil fill. A quality catch can has internal routing in it to remove the vapors. The pathway in and out matter to trap oil. Here is a pic of a Corvette. Note the plug under the side that goes to the intake side of the tb. Since the MM picture has statements about the can only venting through the breather when there is pressure, maybe if the routing is backwards, it's preventing the venting. Without knowing the internals, or viewing a cutaway, idk. And companies like to keep their design a secret. The L99 has the fresh air supply on the driver's side. But be aware, it is taken from the intake tube, after the maf. That way it is metered, measured, air. If you just let unmetered air in, you'd want to tune for that additional air. I'm not sure of your setup and where or if you would be able to tap into the intake routing to have the maf measure your air.

[RupertPupkin]

Originally Posted by Badbubba

1st I would test the catch can for proper operation. The connections on yours are different than the one I posted from their website. The small clear plug, guessing site glass, is below the fitting that goes to the intake side of the tb. Your clear plug is below the fitting that comes from the oil fill. A quality catch can has internal routing in it to remove the vapors. The pathway in and out matter to trap oil. Here is a pic of a Corvette. Note the plug under the side that goes to the intake side of the tb. Since the MM picture has statements about the can only venting through the breather when there is pressure, maybe if the routing is backwards, it's preventing the venting. Without knowing the internals, or viewing a cutaway, idk. And companies like to keep their design a secret. The L99 has the fresh air supply on the driver's side. But be aware, it is taken from the intake tube, after the maf. That way it is metered, measured, air. If you just let unmetered air in, you'd want to tune for that additional air. I'm not sure of your setup and where or if you would be able to tap into the intake routing to have the maf measure your air.

Directly from their website. I texted the flow and suction of the can. It works accordingly.

[RockSVT]

Originally Posted by Badbubba

The L99 has the fresh air supply on the driver's side. But be aware, it is taken from the intake tube, after the maf. That way it is metered, measured, air. If you just let unmetered air in, you'd want to tune for that additional air. I'm not sure of your setup and where or if you would be able to tap into the intake routing to have the maf measure your air.

This is right the clean side should pull air from the intake tube, the dirty side will pull air post TB so it has the most vacuum. It pulls clean, metered air that way through the crankcase that way. Elite Engineering even has a triple port catch can setup to where if you get more vacuum from the Intake tube port than the Post TB port then it will pull vacuum from it instead, so that you're still pulling vacuum even at WOT.

If you want to substitute the clean side valve cover port for the valley cover port you can do that but you can't pull unmetered air from the driver side valve cover and just "tune" for it. The only way I could see that working is if you ditched the MAF sensor and went SD using the MAP sensor only for tuning. Then it would work the same seeing as how its pressure based and not flow based, but that seems like a lot of trouble just to route a catch can different than what's recommended.

Good luck to you guys and your projects.

[IKILLEDSUPERMAN_ZL1]

Originally Posted by RupertPupkin

That is the million dollar question. I would row through gears as much as possible, and hit boost a lot also. Only thing changed was the tune. Only thing I can do now is prevention. With that being said, I think my awesome drawing is my plan of attack. I would add a vented catch can from the clean side to my ECS, but there’s no port to attach to. So I would just add a breather. Should I add a breather on the passenger side valve cover? I saw another forum member here that did it.

That's exactly how I have mine hooked up and my car is tuned with no MAF.

[Badbubba]

Originally Posted by RockSVT

This is right the clean side should pull air from the intake tube, the dirty side will pull air post TB so it has the most vacuum. It pulls clean, metered air that way through the crankcase that way. Elite Engineering even has a triple port catch can setup to where if you get more vacuum from the Intake tube port than the Post TB port then it will pull vacuum from it instead, so that you're still pulling vacuum even at WOT.

If you want to substitute the clean side valve cover port for the valley cover port you can do that but you can't pull unmetered air from the driver side valve cover and just "tune" for it. The only way I could see that working is if you ditched the MAF sensor and went SD using the MAP sensor only for tuning. Then it would work the same seeing as how its pressure based and not flow based, but that seems like a lot of trouble just to route a catch can different than what's recommended.

Good luck to you guys and your projects.

Others have stated on this site that the tune was adjusted and corrected for the open breather. Basically a vacuum leak. The breather will affect the tune mostly at low rpms. That is when you have the most vacuum. I don't like the tuning method. Yes, the reason for clean side can is with the tb open, there is no longer a significant differential pressure. Since both ports are pretty much stabilized, pressure in the crank will push through both sides.

[Badbubba]

Originally Posted by RupertPupkin

Directly from their website. I texted the flow and suction of the can. It works accordingly.

Whelp, there goes that idea. Odd that they swap the ports on some of their cans.

[RupertPupkin]

All good. Appreciate all the feedback.

[RupertPupkin]

Car came back from speed inc, and fixed my crank seal issue. They had plumbed in tubing from the driver clean side to the s/c filter. They also plumbed another set of tubing from the valley to the s/c. I’m assuming I would need another another catch can between 1 of the 2 hoses. If so, between which hose?

[hammdo]

Originally Posted by Bo White

I run 2 catch cans. One dirty side like yours and one clean side like Mighty Mouse suggested.

Ditto for me. Some oil in both cans...

-Don

[eLeSthree]

Are you saying all the oil splatters on your intake and fuse panel came from the front main seal???

It sounds to me like someone F'd your seal when they put the balancer on or during a cam swap. How would a leaking front seal down by the crank get oil all the way up there?

Since you already have the MM wild setup, I would stick with it, and set it up how they suggest. Guys running a shit ton more boost use that without a problem. My guess is boost didnt cause your seal to pop out.