quote:Originally posted by larryw:
Doug said that there is no other place to locate the valve on the Cleveland except into the valve cover.
It seems like the air movement through the system would tend to help drain oil out of the breather fitted valve cover and tend to help hold oil within the PCV fitted cover, netting one generally empty rocker cover and one usually full cover.
Does the PCV system really pull enough vacuum make this happen?
Would there be any advantage to mounting the PCV valve through an intake manifold down onto the lifter valley? Seems like it might help to pull oil out of both heads more evenly, if the effect is truly that strong.
Winter ramblings, below zero again this morning.
The Weber manifold available for this engine lends itself well to that type of a modification relatively speaking. Drill a 1-1/8" hole through the base plate, put a 1-1/8" to 3/4" grommet in the hole, stick a pcv in it.
There are unknowns with it though but it seems that the issue of siphoning oil into the induction through the pcv valve is because it is located in the valve covers and has this very high natural reservoir of oil.
I don't know how much is in a reservoir in the lifter "chamber" of the block but it can't be 3" deep in oil? I don't think so but I can't think of anyone who has talked about that before?
There COULD also be an issue with the pcv valve fitting through the manifold and bottoming out on the top of the block in the valve lifter chamber? I've never measured there for that.
This really is somewhat of a unique issue simply because what race cars are going to use a pcv valve system? Everyone is kind of on their own as a result. There is no one's car that exists that I can copy solutions off of that I have discovered yet?
As I mention in a previous post, locating the pcv in the manifold is a possibility but one that I don't really want to attempt and I do not cherish the idea.
I've been looking at the Trick Flow "oil filler extenders" and would go that route first. The benefit is those would require no further non-reversible modifications.
I can't say definitely yes or no on this because it IS something I am still working on an ongoing basis.
As previously posted though, my initial design is to use two of the "catch cans". One to use as an oil separator on the pcv valve line BEFORE it enters the intake manifold.
The other as a vented catch can to the oil fill tube.
Any race track is going to REQUIRE some kind of catch can system for this car. I'm just attempting to anticipate that and incorporate it into a smooth designed in system rather than a haphazard way of arriving at a solution.
The plumbing on that one is nice and neat and any "mechanic" would instantly be able to read what it does at a glance.
It IS NOT PLUMBED in yet and is going to require SOME testing to see how much oil it skims out of the engine. If it takes too much then I go to plan B...whatever that is?
You are just seeing me think this out in public here a little.
I should also mention that this is all in anticipation of using the E.F.Weber adjustable pcv valve. It's only available one way, and it fits into a 3/4" id grommet, like a SB Chevy does.
