does crankcase need evac system on street with mufflers?

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GEO said:
So how many hours did you waste finding and posting all those pictures?:sign3:
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About 1/2 hour. I guess all these motors are gonna leak oil all over the place and end up with corroded innards? I see hundreds of cars with just breathers and no PCV every week at car shows and cruise nights. Them too?
 
69_340_GTS said:
About 1/2 hour. I guess all these motors are gonna leak oil all over the place and end up with corroded innards? I see hundreds of cars with just breathers and no PCV every week at car shows and cruise nights. Them too?
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What ever you say FOREST:poke:
 
69_340_GTS said:
About 1/2 hour. I guess all these motors are gonna leak oil all over the place and end up with corroded innards? I see hundreds of cars with just breathers and no PCV every week at car shows and cruise nights. Them too?
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Relax, the OP asked what's the best way, best would be a PCV system of some sort like a PCV valve, or draft tube like old 40's / 50's cars, or as you know most hi hp drag race and street engines use a vacuum pump to to keep psi down and to help ring seal.
 
Instead of telling my why there are so many street cars and hot rods running around without PCV, with no apparent problems, including me, all you can do is insult me. If that's all you can do, why bother replying? Calling someone "stupid" or "Forrest" isn't exactly constructive. I thought my answer to the O.P. was correct, because it is done all the time. There are obviously some professional engine builders not installing PCV on their engines. Why would they do that if it is so wrong?
 
stop the drama. PCV is an anti-smog device and it helps keep the crankcase/valve covers cleaner inside and helps keep oil from spewing where it shouldnt.

nobody's callin you stupid. yes it's an optional device. so are seat belts.

During World War II a different type of crankcase ventilation had to be invented to allow tank engines to operate during deep fording operations, where the normal draft tube ventilator would have allowed water to enter the crankcase and destroy the engine.[4] The PCV system and its control valve were invented to meet this need, but no need for it on automobiles was recognized.

In 1952, Professor A. J. Haagen-Smit, of the California Institute of Technology at Pasadena, postulated that unburned hydrocarbons were a primary constituent of smog, and that gasoline powered automobiles were a major source of those hydrocarbons. After some investigation by the GM Research Laboratory (led by Dr. Lloyd L. Withrow), it was discovered in 1958 that the road draft tube was a major source—about half—of the hydrocarbons coming from the automobile. GM's Cadillac Division, which had built many tanks during WWII, recognized that installation of PCV on vehicles could bring the first major reduction in automotive hydrocarbon emissions. After confirming the PCV valve's effectiveness at hydrocarbon reduction, GM offered the PCV solution to the entire U.S. automobile industry, royalty free, through its trade association, the Automobile Manufacturers Association (AMA).[citation needed] The PCV system thus became the first real vehicle emissions control device.
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moparlover said:
stop the drama. PCV is an anti-smog device and it helps keep the crankcase/valve covers cleaner inside and helps keep oil from spewing where it shouldnt. nobody's callin you stupid. yes it's an optional device. so are seat belts.
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No, then what is this:

:sign3:
 
Like Pishta said- gets rid of nasties. If you don't use PCV, change oil OFTEN! Also, carbs are
calibrated to work with the "vacuum leak" of a PCV valve. Not using PCV system can be helpful in getting
big cammed motor to idle better, but, opening up idle feed restrctions in carb is the better way. As for
evac system w/mufflers, sorry to say it, but it doesn't work. Keeps burning out the one way valves and
then blowing the dipstick and gaskets out of motor.
 
A PCV system is far superior to running a couple of breathers. With gigantic breathers like most of the ones pictured you probably won't raise the crankcase pressure enough to cause oil leaks, but that doesn't make it the best way to do it. A properly working PCV will pull a light vacuum on the crankcase, let everything work as its intended, and even clean up the air in the crankcase.

As for all the pictures- A lot of people doing something the wrong way doesn't make it right, it just means that a lot of people are doing it wrong. In this particular case it may not exactly be "wrong", but its not the best way to do it either, and showing that a bunch of people do it that way still doesn't make it the best way to do it. And some of those pictures are ads for crate motors or aftermarket parts, so it really doesn't mean they get run like that. Just that they're "prettier" like that.
 
Stock type engine I agree on the PCV. PCV did not work for me, neither did Multiple breathers on the Valve covers. I even tig welded tubes 4" up off the valve covers then attached the breathers to them. I still had excessive crank case pressure and oil was actually getting into the cylinders past the rings..... Not good for NOS. Engine is a 410 Stroker that I rev to 7200RPM on about a 200 hit of NOS. I had to go with a Vac Pump to get it under control.

So saying that a PCV is the fix all is kind of funny.
 
Mad Dart said:
Stock type engine I agree on the PCV. PCV did not work for me, neither did Multiple breathers on the Valve covers. I even tig welded tubes 4" up off the valve covers then attached the breathers to them. I still had excessive crank case pressure and oil was actually getting into the cylinders past the rings..... Not good for NOS. Engine is a 410 Stroker that I rev to 7200RPM on about a 200 hit of NOS. I had to go with a Vac Pump to get it under control.

So saying that a PCV is the fix all is kind of funny.
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Sounds like a ring seal problem. Are you using low tention rings?
 
PCV costs no power, don't know why you wouldn't run one. Simple and effective. BUT the collector type evac systems don't work well on the street. They are designed to mount into the open collectors of engines that operate at high loads and high RPM. Great for circle track and dragsters. This is a classic case of using the wrong part.

Bolting a race car part on a street car won't always make it "a little more race car," and may not work very well.

BTW the first OEM automotive use of a PCV I can think of valve was 1941. Anyone know of an earlier application?
 
EL5DEMON340 said:
Sounds like a ring seal problem. Are you using low tention rings?
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Yes but I know guys with close to the same set ups and standard rings that have the same problem. Mshred is one of them as well. Pretty sure he has tried it all like me. Last I heard he was going the VAC pump route as well. He too is on the happy sauce.

My issue to be exact is in the higher RPM range. In the lower RPMs the issue did not raise its head. No worries now. The Vac pump is doing its job well. No oil is ever in the holding tank either.
 
I can't believe what I'm reading here. C'mon. Here's a decent treatment of this subject that a ten year-old can follow.

http://en.wikipedia.org/wiki/Crankcase_ventilation_system

As for water in oil or vice versa, it does not mix. Short of running the contents of a crankcase through an oil separator, the most effective way to remove condensation from the crankcase is to bring the engine up to operating temperature and hold it there.

We ran an oil temp gauge in the race car (wet sump) for part of a season. Even after a long feature race oil never exceeded about 230ºF IIRC though it usually ran a little over 215ºF. After this pattern became established, we removed the gauge because it was more of a distraction than anything else. Although the sump would hold 7 quarts of oil, we usually ran it with 4 or 5 in order to keep oil from climbing up into the crank.
 
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