PCV system help for S/C

[jay99914]

I just ordered in everything that I will need for my Vortech V3 setup and it seems like each person has their own opinion on HOW TO and NOT HOW TO run the system under boost, and it is a little confusing to me. Please correct me if I am wrong, and feel free to show some pictures of your setup because that would be a huge help. Also, I apologize for those who are sick of seeing this topic as well.

This is my understanding from what I read thus far;

With a blow-through MAF setup, people either run both sides of the PCV's to a catch-can which is then vented through a filter, but some people say they do not like the smell it gives off, and some say they feel like it is insufficient ventilation for the engine internals. The other method that was mentioned was running the passenger side PCV to a catch can and keeping it plugged into the plenum, and for the driver side, that goes across the engine bay to the inlet side of the S/C. Some people said that is not good because that is not unmetered air on the inlet side now that the MAF is in a different spot. Is there a correct and incorrect method, or is it all personal preference? I understand the objective is to stay away from positive crankcase pressure and that is also my goal.

 

[manicmechanic007]

Need to pass emissions?
I'd run two PCV valves (one in each valve cover) plus a vent
or
Better yet (if no I/M needed) I'd run a crank evac system with one way valves and tubes to the header collectors

 

[Bullitt347]

I understand the objective is to stay away from positive crankcase pressure and that is also my goal.

When the engine is under boost, it is impossible to not have positive crankcase pressure, unless you have a crankcase evac system, which a PCV system cannot do under boost. A PCV valve works off of engine vacuum, which is absent when under boost.

 

[FastDriver]

My turbo cars vent to atmosphere, and the oil vapor is just something I've tolerated for a long time. I wonder if a normal PCV system with a check valve that vents under positive pressure to a catch can would work.

 

[jay99914]

Need to pass emissions?
I'd run two PCV valves (one in each valve cover) plus a vent
or
Better yet (if no I/M needed) I'd run a crank evac system with one way valves and tubes to the header collectors

I do not have emissions testing in my area.

 

[jay99914]

When the engine is under boost, it is impossible to not have positive crankcase pressure, unless you have a crankcase evac system, which a PCV system cannot do under boost. A PCV valve works off of engine vacuum, which is absent

When the engine is under boost, it is impossible to not have positive crankcase pressure, unless you have a crankcase evac system, which a PCV system cannot do under boost. A PCV valve works off of engine vacuum, which is absent when under boost.

So can I just run my tube that comes across the driver side and plugs into my oem intake pipe, down to my power pipe? The only difference is that it will now be before the MAF instead of after it, like oem.

 

[jay99914]

I am going to install a catch-can on the passenger side because it would not hurt to do so, but would hooking the driver side up to the unboosted side be the best way to go? The MAF is going to be In the boosted area more upstream, but atleast there is still negative vaccume in the area between the filter and post supercharger. Think this would hurt anything in the long run? Maybe an idle surge sometimes at best?

 

[jay99914]

So sum this situation up, I decided to go with an evil energy catch can on the passenger side, with a UPR one way ball valve between the lines to ensure no positive boost can push back through the TB (redundant PCV). In addition, I am getting rid of my driver side oil filler cap with a one way valve breather that will release pressure before it builds up too much, but will not pull air in. I am going to keep a closed PCV system but implement fail safe items to ensure pressure will release if necessary.