i currently have my pcv valve plugged up and i put a small breather filter in the front valve cover, i was wondering what you boosted guys do with your pcv valves? i was planning on putting a oil catch can, what do you guys think about oil catch cans? i'm getting alot of smoke coming out the front valve cover where the breather filter is.

 

Why do you have the valve plugged? All I did was put the breather filter on and that was it on my set up. If you are getting blowby then you need a catch can.

 

the guy that did my setup told me i should plug up the pcv valve, i cant find any info on pcv valves with boosted setups . i was thinking since our cars have a pcv valve that just sits on the valve cover with no threads its possible that it can pop off under high boost like 15+ lbs

 

You need a PCV valve. It should not be plugged.

 

Here are your two options with PCV. You can hook it up like stock into the intake manifold and put a filter on the front valve cover.

Or

You can leave the pcv open (no hose on it) and also leave the front valve cover open (with a breather), basically you will have the crank case vented, you will see a little amount of smoke come out, which is acceptable up to a point (now once u close the hood and u see smoke coming out still then u in trouble lol aka bad rings probably)

pro's and co's

the first way, while normal driving, not in boost, the vacum from the manifold will be pulling air in from the PCV, that air will contain the blowby smoke along with fresh air thats being sucked in from the front valve cover (since both covers are connected with a hose towards the timing cover), most of the time this is good because emmissions, you burn up the blowby in combustion, etc... also the con about this is that, it will be sucking in oil as well (that smoke is basically vapors that have oil, when it condenses you will get oil), here is where you need the catch can so it can condense inside the can and not let oil go into ur manifold (might still let oil go in but alot less), During boost, the manifold will develope positive pressure which will keep the pcv system from working, and at this point it will let out the blowby through the breather you have in the front (a possibility is that the crank case's pressure might actually be higher than your boost and therefore it will still be going into the manifold).

the easy way out, do it the second way, u dont have to deal with catch can, or pcv leaking while in boost, etc.., the bad part is that the vapors coming out or the smoke you see, STINKS and WILL get annoying, specially if you pick up your wife/girlfriend and she complains about her hair smelling like oil after u get out the car lol.

for both options, you have to look at your tune, because having pcv hooked up is basically like having a vacum leak (since its pulling unmeasured air from the valvecover/crankcase), disconnecting pcv system will make it rich. these both apply for (not in boost) condition.

BTW, im speaking from experience on this. I went with having it vented, less head ache and the smell is manageable (you can run hoses from valve cover to the back of car or figure something out). If yo u decide to go with vented way. I suggest you take off the hose that connects both valve covers, or if you want, cut it in the middle, put a T and put another filter there. This way when your in boost the crankcase(valvecovers) will let out vapors and blowby as quick as possible, the less pressure in there the better.

Hope this helps, its probably sticky material if a mod is reading this.

 

i have it vented with the vacumm line to the pcv valve plugged up. i 've been driving my car like this for over a year now but my breather filter gets oil on it and starts dripping oil little by little. the smoke is not noticeable unless the hood is open and the smell i've gotten use to lol. i'll try putting another breather filter by the other hose that connects the two valve covers and see if this helps. thanks for the feedback

 

no problem, yea thats the best bet, try to have as many openings as possible if you have it vented, that way it releases the vapors quick and dosnt build up too much pressure in the crankcase.

 

I'm an NA guy so I thought bouncing this idea off you boost experts might give some good input. From reading this thread PCV on boosted engines seems to be a universal issue. My neighbor has a Turbocharged SR20VE Neo with a similar problem. We've looked it over and may have come up with something that may work as an improved solution to plugging the PCV. Short explanation; A standard vented filter on the breather inlet, at the PCV valve outlet install a hose onto a sealed air/oil filter/catch can, and a filter/catch can outlet/vent hose to a fitting close as possible upstream to the blower inlet. The theory is; Crankcase blow-by oil/gases/pressure will go in the filter/can, to prevent oil from going into the blower/inter-cooler/intake, and Blower Suction replaces IM Vacuum for proper flow through the PCV system. The assumed advantage is that crankcase oil/gasses/pressure won't back up/come out the breather inlet, "smoke-stink" will go in the engine/out the exhaust, and Blower Suction/PCV Flow would be highest at boost when crankcase ventilation is most needed. Feedback please!