pvc, can i just but a filter on

[2DaTrakNow]

I was wondering if I could get rid of the line that runs from the pcv valve to the intake, and just put a air filter on the end of it.

 

[2DaTrakNow]

I didn't mean a filter right aftet the pcv valve, but the port that comes of of the head/valve cover and goes to the intake.

 

[bartels903]

I have had it like that on my car thinking it was the way to go without researching. A catch can of some sort would be your best option. The catch can will catch the oil coming out of that line in a canister instead of routing it back to your intake leaving you a dirty mess. I had my little red filter on how you asked for a week or two and it turned a dark maroonish color becuase of all the oil. There is even a post somewhere about how you can take a fuel filter from a certian car and sit it in there and it will catch the oil. (a cheap alternative to a catch can).

But bumping your own thread if you meant to or not is frowned apon here. Just edit your first post next time and if somebody knows the answer they will get to you.

 

[jepherz]

you're introducing unmetered air into the system if you put a filter on the crank case filter and still have the PCV hooked up normally.

 

[oldman]

you're introducing unmetered air into the system if you put a filter on the crank case filter and still have the PCV hooked up normally.

Correct, the solution is to install an inline oil catch can and still route it back to the intake pipe.

 

[nightspeed87]

so the fuel filter idea were one side of the fuel filter canister connects to the pcv port, and the other to the intake arm would work just like a catch can and catch all the oil from going into the intake?
And the added unmetered air is it a significant amount to change anything in your a/f ratio or egt or anything?

 

[jepherz]

^^If you want to keep the system working like it was designed (at idle/vacuum, air is drawn through the crank-case in order to vent out gases) and still keep oil from entering the intake, you need to hook up a "catch can" inline with the hose (between the crank case vent and the intake snorkel). I personally just purchased a cheap fuel filter, cut the hose, and put it inline. I haven't put enough miles on my car to tell you how it is working, but it obviously will catch at least some of the oil and still allow the system to work as inteded.

In response to your question about what the unmetered air will do, probably not a whole lot. It's only going to matter while you're in vacuum. However, it will make some difference as it is basically a leak in your intake. IMO, you should get rid of all of these issues that you can. Our cars have enough issues as is when you start modding the crap out of them; why introduce more?

HTH

 

[bartels903]

so the fuel filter idea were one side of the fuel filter canister connects to the pcv port, and the other to the intake arm would work just like a catch can and catch all the oil from going into the intake?
And the added unmetered air is it a significant amount to change anything in your a/f ratio or egt or anything?

The FF idea is a somewhat "cheapass" way. You get the FF and connect a peice of tubing to the nipple on the valve cover, then you connect it to the one side of FF and then another peice of tubing back to the intake, if I remember correctly.

Adding unmetered air I think would be just like venting to the atmosphere, exept downscaled a bit. Don't quote me on that since I'm not the best with this yet, but I think I am correct, maybe Oldman will chime in, he is an intelligent guy.

Edit- He beat me to it, oh well.

 

[javi-tsi]

Here is a $49 fix. Expensive, but effective.

Quote from RRE: "you have the option of disabling the PCV valve for more crank case pressure relief while making boost"

http://www.roadraceengineering.com/instructions/catchcaninstructions.htm

 

[oldman]

Here is a $49 fix. Expensive, but effective.

Quote from RRE: "you have the option of disabling the PCV valve for more crank case pressure relief while making boost"

http://www.roadraceengineering.com/instructions/catchcaninstructions.htm

Not to take anything from either RRE or Taboo but what they failed to tell you is when using either fuel filter, VTA catch can or just leaving the hose hang, you will be introducing unmetered air to the system via the pcv valve, this is why the breather is connected to the intake pipe in stock form.

As for disabling the pcv altogether, here is a quote from the RRE instruction.

An option for cars that never see use on the streets is to disable the PCV valve. Under normal operation the PCV valve allows crankcase air to be drawn into the intake manifold when you have vacuum in the manifold. Once you make boost pressure, the PCV valve closes and the only ventilation the crankcase gets is thru the small hose that was running to the turbo inlet.

1. They only recommend this setup for track use only. There are real technical reasoning behind this statement, it's not like a test pipe or the likes where it's only for emissions purposes only.

2. I repectfully disagree with their statement "By eliminating the PCV valve you can get twice the crankcase ventilation while under boost.". I think what they meant to say is "twice the crankcase pressure relief", crankcase ventalition is different from crankcase pressure relief. In oder to ventilate a closed enclosure (in this case swapping out the fuel mixture, blow by, with fresh air) you need two exits, one pulling blow by out and one supplying fresh and metered air. Venting both posrts like RRE suggested will only relief pressure, half of the job, while allowing fuel to mix with your oil because there is no vacuum on the system to pull and swap what is building up in the crankcase. Anyone who is running this setup can easily verified this by opening the oil cap after a hard run and observe the amount of smoke/fuel vapor present in the crankcase which will end up settling in your oil.

Also, disabling the pcv valve will immediately change your air/fuel ratio, if you're in near stock form without any tuning or logging capabilities, this option shouldn't even be considered period.

 

[pitbullowner_2]

i think i might have an answer for the fuel filter idea and maybe not introduce any air into the system check this out and let me know if i'm correct, they look like they are enclosed so they "should not" leak

http://cgi.ebay.com/ebaymotors/5-In...011QQitemZ320003149293QQrdZ1#ebayphotohosting

and they are cheap if someone thinks they might work

 

[oldman]

i think i might have an answer for the fuel filter idea and maybe not introduce any air into the system check this out and let me know if i'm correct, they look like they are enclosed so they "should not" leak

http://cgi.ebay.com/ebaymotors/5-In...011QQitemZ320003149293QQrdZ1#ebayphotohosting

and they are cheap if someone thinks they might work

Many are running with similiar inline fuel filter and it does work so it's nothing new . The only thing I'm concerned with is the decrease in air flow capacity once the paper filter is soaked with oil.

 

[dyablo]

i think i might have an answer for the fuel filter idea and maybe not introduce any air into the system check this out and let me know if i'm correct, they look like they are enclosed so they "should not" leak

http://cgi.ebay.com/ebaymotors/5-In...011QQitemZ320003149293QQrdZ1#ebayphotohosting

and they are cheap if someone thinks they might work

I have been running one of those filters on my gst for 2yrs now. I change it out at every oil change 3k miles. It does get a little dark from the oil but not to bad. I have not had any negative effects yet

 

[keymaster]

What's all this talk about introducing unmetered air? If you just run a filter off the valve cover, you can just put a bolt or other plug on the intake, not very hard.

 

[PieEyedPiper]

They dont clog much at all, I can still blow through it relatively easily and mine is 7k miles old.
But I do regularily test it to make sure, restricting that line just makes me feel guilty of something.
They're also 99cents at Napa.

 

[PieEyedPiper]

What's all this talk about introducing unmetered air? If you just run a filter off the valve cover, you can just put a bolt or other plug on the intake, not very hard.

There is not always positive pressure in the crankcase. Meaning, sometimes there is vacuum and it will pull in unmetered air.
That is my understanding. Please correct me if I am wrong.
It is implicit that you would block off/plug up.cap off any unused ports on your intake when doing this kind of thing. You're not going to uncover anything new here though. We have only 2 options.

1. Leave it stock and get an oily layer in your intake pipe, IC, and IC piping.

2. Add a 99cent in-line fuel filter to that line and decrease oily buildup in your intake pipe, IC and IC piping.

Besides, adding an open filter like you suggest will only prove to spray oily mist all over your engine bay. Sooner, rather than later, you'll have filthy, oily engine bay, parts, hoses, radiators, etc etc.

 

[xveganxcowboyx]

Besides, adding an open filter like you suggest will only prove to spray oily mist all over your engine bay. Sooner, rather than later, you'll have filthy, oily engine bay, parts, hoses, radiators, etc etc.

Some people run the line really low so they spray all over the road instead.

 

[PieEyedPiper]

Some people run the line really low so they spray all over the road instead.

ah true enough.
You're still left with un metered air, but at least your engine will stay dry!