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pcv valve mod

Reaper

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The hot air your getting in the intake manifold would barely register so wouldn't even worry about it.

The oil is another matter, though venting to the atmosphere is illegal so perhaps you should look into a catch can. That way at least you are legal.

Not sure that a catch can is legal unless it has a vent at the top that goes into the intake at some point. Not that it would stop me installing a catch can myself as you probably have already broken every other epa law under the sun by that stage anyway :p

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Reaper

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The PCV valve is not the only opening into the crankcase for blowby gasses to escape through. Theres also the air inlet pipe or "engine vent pipe" that supplies the fresh filtered air into the crankcase where it does the job of scavenging any blowby gasses escaping past the rings. Any gasses etc that are scavenged will then get sucked up through the PCV and then fed into the inlet manifold where they are then consumed in the combustion process.
The workshop manuals also say that if the blowby gasses exceed the maximum volume that the PCV can handle, either because of a worn engine, or when the engine is running under extremely heavy loads, then the blowby, as well as being sucked in through the PCV , will also be vented back through the engine vent pipe that usually supplies the fresh air into the crankcase, it can then be drawn into the engines intake air where it can consumed in the combustion process.
Years ago, I used to see a lot of engines that had a pipe that just vented the crankcase fumes to the atmosphere, which was obviously not good for the enviroment, so they came up with the idea of sealing up the crankcase, introducing fresh air into the crankcase and then drawing it out again through the PCV valve to keep a constant flow of frech air through the engines crankcase for scavenging purposes.
If a crankcase was completely closed off to the atmosphere with no PCV system working, then the engine will most likely build up too much positive crankcase pressure and blow out an oil seal.

Nah - just pop the dip stick a bit and vent from the dipstick tube :)

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drewVHSS

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Nah - just pop the dip stick a bit and vent from the dipstick tube :)

Reaper

Old trick i learn't in car yards with 80's and 90's toyota's is to lift up the dipstick and due to a vacuum.. engine then runs rough.... easy bargaining tool for a cheaper price!!!!!!
 

Brett_jjj

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Removing the dipstick or opening the oil cap with the engine running, usually wont cause the engine to idle badly unless the PCV valve is buggered and cant control the airflow passing through it properly, as the the PCV valve only allows a certain amount of air to pass through it into the inlet manifold,and when its working correctly, it is not enough air to cause any idle problems with the engine or whatever.
 

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Vent both rockers to a catch can with a filter on top. Change your oil every 5000km and no need to worry about moisture buildup. Avoid cluey police lol

Completely pointless. If the catch can is vented we're back to square one with the setup being illegal. He may aswell just put the vent on the rocker cover.

Not sure that a catch can is legal unless it has a vent at the top that goes into the intake at some point. Not that it would stop me installing a catch can myself as you probably have already broken every other epa law under the sun by that stage anyway :p

Reaper

Yeah, I should have made that clearer. A seal catch can is what he is after like the Elite Engineering one I have. Dirty air from crank case goes in, oil condenses on baffle, cleaner air goes back into intake manifold.
 

GRPABT1

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A sealed can is pointless in a performance application. The motor won't be able to breath enough with the crank case vented back to the intake through some piss ant factory line if it is modified and raced. And it will still carry oil vapor back into the intake tract reducing octane. I've tried even fancy custom made catch cans with all the baffles and steel wool etc and they still puke into the intake and the pressure still builds up blowing the dip stick or oil seals. Their isna reason race cars vent to atmosphere, it's because it's the only way that works at those levels. So as mentioned previously it is a pointless exercise full of headaches unless you just go a vented can. Yeah it's illegal, not everyone cares about that. If you are worried about legalities then I suggest you find a different hobby.
 

GRPABT1

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And where did he mention that he was after a sealed can or even worried about the legalities? And the filters directly on the rocker are messy and a potential fire hazard as they often spill oil out of them
 

Jesterarts

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A sealed can is pointless in a performance application. The motor won't be able to breath enough with the crank case vented back to the intake through some piss ant factory line if it is modified and raced. And it will still carry oil vapor back into the intake tract reducing octane. I've tried even fancy custom made catch cans with all the baffles and steel wool etc and they still puke into the intake and the pressure still builds up blowing the dip stick or oil seals. Their isna reason race cars vent to atmosphere, it's because it's the only way that works at those levels. So as mentioned previously it is a pointless exercise full of headaches unless you just go a vented can. Yeah it's illegal, not everyone cares about that. If you are worried about legalities then I suggest you find a different hobby.

Are you suggesting that a catch can on a VT v6 is what you consider a "performance application" ?!? lol.

Mate, atleast make what you post relevant to the thread.

I have a sealed can, I am yet to have the any headaches with it. It's on a cammed LS2 so I guess that considered more performance than the OP yet no issue... hmmm...

I can see that in YOUR experience it hasn't worked, but perhaps that's becasue a) you clearly don't know what you're on about or b) you made the catch can and it was ****? lol.

And where did he mention that he was after a sealed can or even worried about the legalities? And the filters directly on the rocker are messy and a potential fire hazard as they often spill oil out of them

The OP never said he was worried about legalities, but why would be do it in a way that is illegal when he can acheive the same result legally? That would be stupid and anyone who would suggest doing something illegally instead of legally for absolutely no gains would also have to be rather stupid... oh wai... that was your suggestion wasn't it?

*awkward*
 

GRPABT1

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The "performance" application is when old mate thinks his V6 is a race car and revs the **** out of it, which will happen or he wouldn't be on this forum asking these noob questions. I could have just said, it's pointless on a shitty stock V6 just dont flog it, be we all know that won't happen and would probably just inspire ignorance from the OP.

And when you get out of the cheque book racer stage and into the point where bolt on goodies don't quite cut it anymore perhaps then you can question if I know what I'm talking about. #### it makes me laugh when people buy a product and automatically think it's the duck's nuts.

Perhaps you'd like to question Pavtek on the subject? Because it's a requirement of warranty on their motors that an adequate breather system be fitted. Like I've said, race cars run ventured cans for a reason, they work and factory PCV systems do not, other than when pootling along as the manufacturer intended.

Lack of proper crank case ventilation can cause problems that don't always rear their ugly head immediately. Oil seals will normally take time to blow out on anything but a race car. But test the limits of the factory PCV system and it will happen, just ask countless commodore owners with leaking rear mains among other leaks.
 

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The "performance" application is when old mate thinks his V6 is a race car and revs the **** out of it, which will happen or he wouldn't be on this forum asking these noob questions.

If we're assuming this is how the OP drives then a) Its safe to say performance of vented vs seal catch cans are the least of his worries and b) When he gets pulled over and is asked to pop the bonnet it would be a better idea to have a legal setup over an illegal setup don't you think?

And when you get out of the cheque book racer stage and into the point where bolt on goodies don't quite cut it anymore perhaps then you can question if I know what I'm talking about. #### it makes me laugh when people buy a product and automatically think it's the duck's nuts.

Once again, we're not builting top fueler buddy. We're talking about cars of weekend hobbist and for those applications seal catch cans are very good.

I think it's funny when people buy something and automatically thing it's the "ducks guts" too.

Thus why I installed my catch can after spending considerable time researching the concept of the product itself and then the various available brands.

Then, I didn't talk the product up until I had personally seen results using the product.

General concensus from weekend hobbists, weekend drag racers, performance shops, etc from around the world is that sealed catch cans do a fantastic job. Apparently you know better but have yet to actualy provide any evidence to show all of the above people, including my self, are wrong.

Finally, Pavtek, once again... have you looked at their site? They don't exactly build engines. They are professional engine builders and their engine are high performance.

Their engines vs the engine in the average "cheque book racers" car are chalk and cheese.

Yout posts are completely irrelevant. You may aswell start telling the OP that they should be running pure alcohol because Pavtek makes engines that run it.

I don't need to go past my "cheque book racer" stage because I'm quite happy with my engines performance. Does what I need it to so I'm not going to spend time and effort running bits recommended for a built engine on mine since there is not point.

Though I would be interested to know what you are running that is so much above and beyond the rest of us meer mortals quivering at the sight of you on your high horse?
 
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