You can put one their but DO NOT put an air filter on it. That will be a huge vacuum leak.

 

http://www.dsmtalk.com/forums/showthread.php?t=177223&highlight=catch+setup

There is a LOT of info in that thread.

 

between the intake tube and valve cover breather

Yes.

 

Proper way*

If only one CC

PCV->IM
Breather -> CC -> intake pipe.

Oil in IM = No big deal.
Oil in IC = Very big deal.

If use 2nd CC
PCV -> 2nd CC -> check valve -> IM = clean IM and no leaky PCV.

Basically, you need the check valve in between the Intake Manifold and PCV. Also, a vacuum source (typically the intake pipe) is important to relieve crankcase pressure and reduce blowby under boost.

 

Proper way*

Basically, you need the check valve in between the Intake Manifold and PCV. Also, a vacuum source (typically the intake pipe) is important to relieve crankcase pressure and reduce blowby under boost.

Hate to bring this thread up but i am trying to route my vacuum lines correctly and wanted to know if the 2nd catch can is necessary? The one that runs the valve cover hose with the pcv to the catch can then to the check valve and to the intake manifold? If 2nd catch can is not needed can i just route the pcv valve to the intake like factory?

Also would you guys recommend that both catch cans should have no breather valves at the top? Both systems should be enclosed, correct?

 

Ok, so between the valve cover breather and intake tube with NO breather.

Right?
My friend runs the same but instead of a breather he just has an open vacuum port and it works for him.

 

lol what about those of us using...say -8 an lines/fittings off the valve cover to the catch can..?

 

I get it now.
From pcv to catch can to intake manifold MUST use a breather.
From valve cover breather to catch can to intake pipe must NOT have a breather.

 

Wrong. They both should be sealed, with a check valve in place, just like the picture above. This is, of course, if you are trying for a modified 'stock' setup. If you are running vents from the valve cover, and eliminating the pcv and breather lines, you should run a vented can.

 

The pcv is a check valve, its just a ball and spring in a tube.

 

The pcv is a check valve, its just a ball and spring in a tube.

Correct the pcv is a check valve, a very shatty one at that. Aftermarket ones are often bad out of the box, and oem ones can go bad after a few thousand miles. Definitely have to have a us plastics check valve or some sort of check valve in place.

 

I'm going to have a custom one made that will be non vented and go between the intake tube and valve cover.

 

I didnt want to post in the CC thread since it has been dead since '08 so im posting it here. Did anyone actually eventually measure the vacuum at the intake pipe? I bet it is minimal. With the VC breather to atmosphere, if the crankcase somehow becomes pressurized that PRESSURE is going find a way to level with atmospheric, so to relieve itself it is going to go through the vent on its own. The mininal amount of vacuum helping it on a stock set up is more than likely for emission purposes.

 

What is in the catch can that prevents the oil from going back into the intake?

 

Gravity.

 

Do you need a catch can or can you just run a vacuum hose with check valve to the manifold?

 

Depends on where the hose is coming from.

Some one put up a diagram that really should have been the end of this thread. It answers everything.

 

So where do you get that plastic check valve from? Can I get one from my local napa or carquest?

 

Yes, but why when you can have a nice one made out of aluminum.

 

Aluminum ones are expensive and take up a lot of space. I use a small fuel filter between my VC and my intake pipe. Doesn't exactly look beautiful, but it does the job for the most part.

 

I bought the us plastics check valve. 4 of them actually and they came in the mail today.

Those m'fers are solid. The only concern I have is how will the plastic and seal react with 200 degree oil. Anyone have any experience with this?

 

I've had one on my car for almost a year and it's had no issue now. The only one I use is between the PCV and manifold. It's one of the ones from USPlastics.

 

Nice, thats what I was looking for^^

 

Anybody know how well the ebay catch cans are? I dont see how you can have 150 into a catch can from sard or greedy or all those other places. It really is just a box with a inlet and outlet. Right?

 

Who has $150 catch cans? JMF's aren't even that expensive. For what it's worth google home made catch cans. You can use a pepsi can if you like. I'm having tbtalon94 custom make mine and he is only charging me $65.

 

You can use pretty much any brand catch can. They all catch oil, so they all do the job they were intended to do. Its not a turbo, so cheaper is better.

 

I'm just using the ac reservoir after I polish it and put some an fittings on it.

Actually I just checked out some of the ebay guys and I may go that route.

 

There is three ways I've seen done seal and unsealed. Sealed and routed back into the intake is the best method. The intake creates vaccum in the crankcase which I heard allows the rings to seal better. Some ppl buy two long lines of tubing ($2) connected to the valve cover and just routed them straight to the ground.

 

I tried this on another car I had. Removing the pcv and letting it vent killed my mpgs. So That is what I mainly want to run the catch can on. A vented can would work better for the one that routes back to the intake pipe. The reason I was asking about the ebay ones is that Ive read some reviews and some seem to create vacuum leaks when they are hooked up. Nothing a little welding cant fix I guess. Yes I have really seen name brand catch cans go for that much. So ebay it is.

 

Not all oil is caught in the can, that is unless you buy a baffled can. I had a greddy can and it caught some oil, but some still made its way back into the intake, I cut it in half and added a baffle and then it was all good,but I'm working on a oil catch/seperator can that not only catch's the oil, but will return it to the pan.

 

OOO I would love to see how you do this, post pics when your done please.

Well tbtalon04 came through again and my catch can is on it's way. Mine is the right and his is on the left. This was made to MY specs and is baffled.

 

Why not just block the port on the intake manifold, remove the PCV valve and use a barbed fitting in it's place. Attach a line to the barb, attach a line to the breather vent on the side of the valve cover, then run those lines into a sealed catch-can. Then run a single line that is at least doubled the size of the 2 lines coming in and run that to your intake pipe.

Should be great crankcase ventilation with some additional help do to the vacuum from the intake pipe.

Wouldn't this also be considered an alternative, but "proper" way to run a breather and catch-can set-up?

Granted this will ONLY be considered "proper" if your not using a mass airflow sensor............AKA Blow through set-up, etc. or whatever, as long as there isn't an airflow metering device pre-turbo.