Modified PCV trap

[flapdoodle]

I wanted to add a PCV filter trap to my list of FE mods, but reasoned that it might be better to place it between the valve cover and the PCV valve to help keep the valve clean and functioning.

http://flapdoodledinghy.com/PVC_trap.html

[GasSavers_TomO]

I like it. nice little write up as well.

[kamesama980]

yep. add provisions to check the level and empty it though. I know from experience. also search for oil catch can as they're known in the performance world.

[8307c4]

Oh, that might work, depends what you're thinking.

One thing I did is bought a high performance breather cap so as to keep the engine from sucking air out of my intake.

I don't have pictures but on OEM breather caps there is usually a rubber hose that leads to the air intake of the vehicle. This hose allows the engine to suck clean air that it needs (for some unknown reason lol) but my problem with this is that it is taking this air from the throttle body! That is, this air it is taking is also intended for the cylinders, it's already past the filter and it should be heading into the combustion chamber but I've got this little hose that constantly is drawing some of it out.

With a high performance breather cap this assembly gets its very own tiny little air filter, thou you do have to make sure to plug up the hose or the outlet from where the hose gets disconnected so that the air intake is air tight again.

Voila, your engine no longer sucks air out from your intake via the valve cover.

[flapdoodle]

That was something I was wondering about. Mine has a little pad inside the air cleaner housing that is supposed to filter. I have doubts. Will look into it. Thanks for the input.

[kamesama980]

you need to clarify what you mean by the engine sucking and whatnot.

couple principles and ideas I've messed with on a couple forums with several engines.

the vast majority of airflow in the crankcase comes from exhaust blowby past the rings. the crankcase will not suck air from the intake. likewise, it does not pull in dirty air from anywhere unless you have a leaking hose or seal...badly leaking. you'd be losing oil so bad it's not funny! to keep the crankcase from pressurizing and pushing seals out, it needs a breather. in the old days, this was done with a simple breather and filter. then, they moved to plugging the PCV hose to the intake. that results in a dirty intake but all the bad gasses get burned and go out the tailpipe. this has an added benefit of putting vacuum in the crankcase to help keep oil from leaking out the seals. the only problem is now you have oil vapor, liquid and a bunch of other crap building up in the intake. to solve this, some people introduce the oil trap, often called a catch can. gasses from the crankcase hit the large space and slow down (fluid dynmics 101) solid and liquid crap settles out and much cleaner air goes through the intake. marginal cleaner exhaust and no crud in the intake.

in short, you want one hose going from the crankcase to the catch can to the intake. if you have a second hose going into the crankcase, leave it in place (the regular foam filter is fine) or block it off completely. you could add an aftermarket filter there but it won't help much.

[GasSavers_SD26]

On some motorcycles, there's a valve system in the exhaust port that we've used to reduce positive crankcase pressure. In doing so, it has netted HP on a dyno and it can be felt through the seat.

In drag racing, some actually use an electric pump to evacuate out the crank case pressure.

[ZugyNA]

I know of someone who gained around 10% mpg by running 7" HG in their crankcase...I think with a van.

I was testing this with my car, but was seeing the vacuum in the crankcase jump up to some pretty high levels..and was afraid of the seals (main and cam) not getting enough oil.

Thinking of using this:

http://www.harborfreight.com/cpi/cta...emnumber=90590

...to try and regulate the vac at around 7" hg.

The setup for the Condensator says to always have the PCV valve between the Condensator and the crankcase...in order to have a partial vacuum in the Condensator...since it is supposed to function as an auxiliary carb.

[flapdoodle]

Thanks for making me aware of the Condensator. There is a difference that maybe require it to be installed the way you mentioned... it has a fresh air port on Models A & B. Other than that, I can't comment since I have never seen one.

[ZugyNA]

The one with the fresh air port is for pre O2 engines. They recommend guarding against having ANY vac leaks when using these with an O2 equipped engine. They now cost $200 or so.

Far as I can tell they are designed to separate combustible gases form the PCV mist. Might seem easy in theory...but it's actually a smoke...very fine particles. The Condensator uses several techniques to separate usable fuel from the heavies.