OK I have searched this topic, and every time I think I understand I read another thread about running a metco breather vs a catch can setup.

What is the end result? Who is running what with a blower setup?

My setup will be an iron 408 with the F1 pushing about 14-17psi. This will be a track/street car (50/50)

Should I run:

LS6 PCV setup

LS6 PCV with a Metco breather

Stock LS1 PCV with a catch can

Stock LS1 PCV with a Metco breather

Someone please help me.

 

This thread helped me out a lot. Lots of other threads referanced inside it also.

https://ls1tech.com/forums/forced-induction/386114-i-know-has-been-discussed-lot-but-what-best-pcv-method.html

 

From talking to Stenod.... ill be running a catch can.....
Kyle

 

So Stenod just uses a catch can?

 

my set up is prety simple. no pcv valve at all. just a 1/2" line from one valve cover to a catch can and then the line from the catch can to a fitting right in front of the turbo. thats all i have and it seems to be working prety good.

couple of negatives are a slight amount of oil still finds it's way into the intake track. the other thing is during the winter the catch can fills with water(condensation) prety fast.

 

Intake or discharge side of the compressor?

 

to the intake side, under boost there is probably some prety good suction there.

 

Wow, I was just thinking about running something like this. You say you use a catchcan and still get a bit of oil sucked into the intake? do you think there is a way to stop that from happening? I figured that a catchcan would prevent oil from getting into the intake for the most part...

 

Let's look at how the stock Syclone/Typhoon system is setup since it is what I am duplicating on my turbo LS1 project:

There is a "T" fitting on the passenger valve cover. The bottom of the "T" is in the valve cover and at each end of the top of the "T" is a PCV valve. One is routed to the intake manifold and one to the intake BEFORE the turbo. This allows for vacuum in the crankcase during vac and boost. Remember that, under boost, everything AFTER the turbo is positive pressure, everything before the turbo (intake pipe) is negative pressure (vac).

On the driver's side valve cover there is a breather that allows air INTO the crankcase.

I ran clear hose at one point from my PCVs to their locations mentioned above, and the intake manifold line got more dirty than the turbo line did. This of course is due to being in boost for a small percentage of your driving time. I will put a catch can on the PCV valve that runs to the intake manifold and a small inline filter on the PCV running to the turbo.

Hope this helps with the big picture.


Tyler
'92 Typhoon
'95 240SX

 

so you used a check valve on each line aswell to prevent air from being sucked into the crankcase when the opposite line is being used?

 

A check valve isn't needed. There is a piece inside the PCV valve that is closed unless there is a vacuum pulling it open. When you are in boost, the turbo PCV is providing vacuum and the manifold PVC is in boost, so there is a pressure in that PCV line keeping the piece inside the valve seated and closed.

Air will be sucked into the crankcase thru the breather in the other valve cover. This keeps a nice flow of air thru the system.


Tyler
'92 Typhoon
'95 240SX

 

Well after alot of time on this I have a catch can. And breathers on both sides.

 

We just use a catch can with a built in breather. Run a line off both valve covers down to it. It's the best way to allow the oil vapor to not blow the filter element apart. It's worked great ever since we started doing that.

 

Hm... Do you have any pics of this setup? Sounds pretty interesting.

 

Thats what we use with cars pushing more than 10lbs.No chance of oil ever getting in the intake

 

i would like to see a picture of that catch can too. where can i get one?

 

Im almost 100% sure this is what they are talking about.

http://www.jegs.com/webapp/wcs/store...tegoryId=16163

 

so with that setup you have no line going to the intake at all? how are you getting any suction from the crankcase?

 

for the catch can you listed from Jegs how would i know to get the 1/4" or 3/8"?

 

You would probably want to get a 3/8" one from Jegs. Then use a 3/8 to -8 or -10 fitting. We use the Peterson version of that. It's nicer because it's all aluminum and we just weld the -10 fittings right to the can. Then you simply put a line up to each valve cover. Technically you only need one, but we usually run one off each side. You can see them in this picture here. They are the lines that go in to the valve cover. We have a welded baffle on the inside of the valve cover to keep a lot of solid oil from getting tossed into the lines. Then, that line goes to wherever you can best fit a catch can. We hide ours.



If you really want the best setup, get a Moroso vacuum pump and then run that to the catch can. That will greatly reduce crank case pressure for you. You do not want to let the motor be your vacuum pump for you. Either get a real vacuum pump or let it vent to atmosphere. If you do run a vacuum pump, make sure you get a vacuum regulator for the motor and install it where you can best fit it. It will help prevent you from drawing too much of a vacuum.

Let me know if you have any other questions.