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Wagner PCV valve

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Looking for input/comments/suggestions, particularly if you’re cammed up and turning lots of rpm.
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If I were to install an air/oil separator in my car how/where would I get the oil back into the engine? New fitting on a rocker cover? I am not very happy with my power brakes and considering an electric vacuum pump. Perhaps a circuit using a PVC then through a separator and then using the pump to support the PVC and the brakes?
 

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1965 Mustang GT. 11.898 @ 113.646, all motor, three pedals
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Discussion Starter · #42 · (Edited)
If I were to install an air/oil separator in my car how/where would I get the oil back into the engine? New fitting on a rocker cover?
It doubles as a catch can. It does not re-circulate the accumulated oil, you just dump it periodically. Provided that the PCV valve is baffled properly, it doesn’t accumulate much oil, maybe an ounce or two every 500 -1000 miles.

I am not very happy with my power brakes and considering an electric vacuum pump. Perhaps a circuit using a PVC then through a separator and then using the pump to support the PVC and the brakes?
That^ sounds good to me, but maybe run that past Jim and/or other guys running Webers
 

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Discussion Starter · #43 ·
Just a warning on seperators/catch cans: If you’re plumbing it between a PCV valve and a manifold vacuum source, do not use an open/vented separator. Manifold vacuum will pull air in through the vent which throws your fuel curves off (lean). They can also puke oil everywhere. They’re cheap for a reason; stay away from those.
 

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Discussion Starter · #44 ·
@BlackStick

Just a thought… and I don’t mean to piss gasoline on a fire… but getting rid of that power brake booster would greatly simplify your specific deal.
 

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Exactly, and VACUUM is simply NEGATIVE pressure. LOW vacuum, HIGH velocity.
Sorry for going of topic but when you say low vacuum, do you mean low pressure? To me, high vacuum is low pressure. Like tuning your idle screws for highest manifold vacuum = lowest pressure

I know I sound like a wise ass now, but negative pressure doesn't exist. I know what is meant and I used to say it too, until a teacher pointed out to me that it was wrong.
 

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Pressure is anything above zero. Vacuum is anything below zero. Zero is the absence of pressure or vacuum.

One inch of mercury equals 0.491154 pounds per square inch whether you're measuring vacuum or pressure.
 

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I think this is more an "argument" about definition than about physics. Out of curiousity, when I would install an annular booster in a carburator that increases the air flow velocity through it, would you say that the vacuum at the suction hole(s) to the jets has gone up or down (i.e. more or less vacuum)
 

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I think this is more an "argument" about definition than about physics. Out of curiousity, when I would install an annular booster in a carburator that increases the air flow velocity through it, would you say that the vacuum at the suction hole(s) to the jets has gone up or down (i.e. more or less vacuum)
The annular discharge booster doesn't increase airflow velocity any more than a straight-leg or down-leg booster of the same dimensions. The difference is in the multiple, small discharge holes around the inner part of the venturi that produces better fuel atomization than the other types. As far as vacuum at the "suction holes"... Don't confuse manifold vacuum, created by the movement of the pistons within the cylinders, with the venturi effect. They are two different "animals". One is responsible for drawing a fuel/air mixture into the cylinders, through the intake valves. The other is the pressure differential created by slowing down airflow using a restriction and using that differential to siphon fuel from a reservoir (float bowl). They are, for all intents and purposes, independent of one another as a large volume of air passing through the intake manifold and into the cylinders may result in a low manifold vacuum because there is low restriction (throttle plates open) that same flow of air passing through the restriction of the venturi will cause a large pressure differential from atmospheric pressure. Remember that the air does not remain restricted...after passing through the venturi the space widens and the air, once again, slows down.
 

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OK, the annular booster was not the best example. How about an airplane wing: speed up the air on the top side, pressure on the top goes down, wing goes up.

About the rest, I know all that. But the discussion was about vacuum in the crankcase and how that helped with reducing oil leaks. I then said that effect will be very low at WOT, because there's very little manifold vacuum at WOT. Then you brought in the Bernoulli effect but in my opinion you mixed up high and low vacuum and how it correlates to air velocity.

But let's not dillute this topic any more with this side discussion ;)
 

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OK, the annular booster was not the best example. How about an airplane wing: speed up the air on the top side, pressure on the top goes down, wing goes up.

About the rest, I know all that. But the discussion was about vacuum in the crankcase and how that helped with reducing oil leaks. I then said that effect will be very low at WOT, because there's very little manifold vacuum at WOT. Then you brought in the Bernoulli effect but in my opinion you mixed up high and low vacuum and how it correlates to air velocity.

But let's not dillute this topic any more with this side discussion ;)
LOL. One last shot....

At WOT (low vacuum), air flow, in terms of the volume of air moved and its velocity, is at its highest.

At IDLE (high vacuum), air flow, in terms of the volume of air moved and its velocity, is at its lowest.

VELOCITY is only possible when there is a pressure differential, otherwise the air mass is "stagnant".

VACUUM is created by placing a RESTRICTION in the path of the mass, SLOWING its VELOCITY. A perfect example of this is a carburetors throttle plates. When closed, vacuum above the throttle plates is nil, and there is not enough vacuum to pull fuel through the booster. Below the throttle plates the vacuum is high, and the pressure differential pulls fuel from the idle discharge holes. When the throttle plates are opened and the restriction removed, the pressure differential between above and below the throttle plates disappears and now its a differential between the intake vacuum and atmospheric pressure, pulling large amounts of air through the carburetor.

"Manifold Vacuum" will vary, depending on where it is measured. It will be highest directly below the throttle plates and lowest as it exits the manifolds intake ports. This pressure differential is responsible for forcing air into the cylinders when the intake valve opens. In fact, when the intake valve is closed, the velocity of the air mass will actually build positive pressure on the back side of the intake valve under large throttle openings as air piles up waiting to get in.

At WOT, and with the PCV valve open wide, you're going to get the maximum amount of crankcase blow-by evacuated due to velocity, not vacuum.
 

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Discussion Starter · #54 ·
Alright, enough of the d*ck measuring contest, you BOTH bring a lot to the table. More than the majority of members here. I learn a lot from you both, so don‘t go getting pissed at each other and then stop coming around 😊
 

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After reading all that I now have a headache, is that due to pressure or vacuum or just being married? :oops:
 
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After reading all that I now have a headache, is that due to pressure or vacuum or just being married? :oops:
Or maybe its the pressure of being married in the vacuum of love? - ugh that was bad lol - but forgive me for that as I 'was' married..lol
 

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OK, I will respect the topic starter's wishes and will reluctantly resist the urge to fire back ;)

One last question though, just because I wonder what you mean:

At WOT, and with the PCV valve open wide, you're going to get the maximum amount of crankcase blow-by evacuated due to velocity, not vacuum.
What velocity do you mean, of the air flow through the throttle bores?
 

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OK, I will respect the topic starter's wishes and will reluctantly resist the urge to fire back ;)

One last question though, just because I wonder what you mean:

What velocity do you mean, of the air flow through the throttle bores?
Yes. The speed of the air, in feet per minute, times the volume of the air, in cubic feet, is going to equal "CFM" or Cubic Feet per Minute.

FWIW, not "mad" at all... maybe CRAZY but not mad. lol. Enjoy a theoretical discussion about hot air, when it doesn't involve politicians.
 

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Come on guys, we all know the only really important question is, "What is the air speed velocity of an unladen swallow?"
African or European swallow?
 
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