i heard that u can swap you pcv valve for a breather is that true and witch 1 is better. and does driving with your back sliding window open really get you worse gas mileage b/c it messes up the air circulating in the bed

 

Yes you can put breathers on. Keeps the intake runners from getting blow-by all over them.

If you want your back window open, open it. Life is too short to worry about worse gas mileage because your rear slider is open. lol

 

If you remove the PCV, how is the crankcase going to be ventilated? The removal of those blow-by contaminants is important and the PCV valve does that. Your engine is designed to use a PCV valve, don't try to re-engineer it.

 

You replace it with a breather. Either a breather placed on top on the PCV where the vac line goes or a breather with a valve inside the acts like the PCV. Either one will work just fine. Its no more re-engineering than replacing the air box with an aftermarket intake.

 

If a breather is a device that allows the crankcase to be open to the atmosphere, you are defeating the purpose of the PCV valve that purges the engine of harmful combustion deposits.

 

Normal 0 false false false MicrosoftInternetExplorer4 Style Definitions table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:"; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Well to each his/her own but after replacing the vacuum line on my 91 with a breather, I no longer had brown buildup on the throttle body. Never had any problems and the only maintenance I had to do from that point in was replacing the breather every year when the filter material became dirty.

A breather is an Open Type on PCV system and the standard PCV system on our trucks is Closed Type PCV. The ONLY difference is that your engine is not burning the harmful deposits and vapors the engine expels. Instead it is being released into the atmosphere. So technically unless your engine is shot, or just worn out, there will not be enough blow-by and vapor buildup to hurt anyone or anything. Actually it’s the difference is nothing more than running your truck without cats, or other mods. It modifies performance at the expense of your vehicle causing more pollution. Just like anything else you do to your truck. In the same matter of speaking this is about the same “reengineering” as replacing your air filter with a K&N, you might be well within the engine parameters with the added air but you’re not in the “pollution comfort zone” as much as you are with a stock filter, even more so with a CAI. Ok I’m done.
Reference:
http://www.filtercouncil.org/techdata/tsbs/94-2R1.pdf

 

The link you posted explains just how important it is to have a properly operating PCV system. Just venting it to atmosphere won't purge the crankcase of harmful blow-by that even happens on engines in good shape. You need a flow of air through the engine. The original poster asked about replacing his PCV valve with a breather, no flow of air here. Go ahead and re-engineer your vehicle (since you are obviously smarter than the people who designed it), don't complain to anyone about the possible unsatisfactory results.

 

All arguing aside (please) and all environmental concerns aside...

With the PCV setup, any blow-by basically ends up in the intake manifold. The intake manifolds then get coated BAD with the blow-by from these engines. So adding the filter on the valve cover on the drivers side (replacing the line running TO the PCV) would at the very least keep the blow-by in the head and prevent the blow-by from entering the intake manifold. On the passengers side I have it running to a catch can. And I'll tell you - the stuff that drains out of there I'd prefer not be in my intake manifold.

But I'm also wondering if the original poster meant to ask if he could put filters on the valve covers - NOT in place of the actual PCV valve.

 

Here is my take on it, I would like to say is why would you want to have that crap from the engine to go through it again. I have seen many motors that have an air pump that presurizes the block to help with the blow-by. So if you put pressure behind the piston, then it helps to eliminate the blow-by period.

That being said. I don't agree with having a breather on the valve covers to vent the blow-by on the newer motors. Now if they are heavily modified then you may want or need to mess with the "blow-by evaporation system". That would be on a case by case basis. As a general rule for me at least, I would say to leave it the hell alone unless you are improving it! If not, GM won't fix it! New trucks don't need it anyways like what was already mentioned. "The newer motor shouldn't have blow-by" But why change it if you don't need to. If you have a lot of blow-by then you have more to worry about than a stupid little PVC valve!

Now I am good!

 

Man was there some venting going on or what? I like it. An angry discussion brings out some interesting thoughts, ideas and descriptions.