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Discussion Starter · #1 ·
I live in alberta and they don't do smog or anything for that matter. I can sell a car to someone without a safety and he could drive it after he gets insurance.

Anyway I was wondering If you can bypass the pcv system on our cars? For the passanger side one that goes to the throttle body can I use a breather? Then plug the throttle body? I just cleaned my trottle body and intake today which had 130000 miles of pcv gunk in there. Improved seat of pants now with it being super clean. Actually aluminum in there, not just brown gunk. And if I can do that to the one side how would I do it to the other? I never did follow the tube for the pcv into the manifold? Are there any sensors that would be mucked up if I did it? I would like to keep the manifold nice and clean inside. I'd like to do it before I get my motorvac done. Any ideas? I used the search feature and came up with nothing. Any ideas?
 
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Discussion Starter · #2 ·
dont do it. (I had a good long friendly explanation of why you should not bypass your PCV system but that was when the impalassforum.com server crashed and killed my post in mid air).

Short answer, Don't do it.
The passenger side is fine to delete, like you did, since that is only fresh air supply for the PCV and blowby into the intake at WOT. But the drivers side is the actual PCV and you'll want to keep that in tact, or else you'll get oil seal leaks and other bad leaks.

Karl
 
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Discussion Starter · #3 ·
I don't mean to block off the pcv but could I put a breather there so the gunk doesn't go into the intake and the pressure is still releived for the crankcase.

Still a no?
 
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Discussion Starter · #4 ·
Still a no.
If you put a breather in place of the PCV valve, you'll have no vacuum for the PCV.

but the passenger side is a yes. That's an emmissions tamper so just be aware of that. For off road use only.


Karl
 
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Discussion Starter · #5 ·
<BLOCKQUOTE>quote:</font><HR>Originally posted by Karl Ellwein:
The passenger side is fine to delete, like you did, since that is only fresh air supply for the PCV and blowby into the intake at WOT.Karl<HR></BLOCKQUOTE>

You are referring to replacing the intake tube with a breather, and not just plugging it.

But the drivers side is the actual PCV and you'll want to keep that in tact, or else you'll get oil seal leaks and other bad leaks.

IOW, you are keeping pressure in the block to a minimum. With the above stated, the oem system is a part throttle/non wot system. Where you need it more actually, (for ring seal) at WOT, you don't have it. That is the reason for the accumulation of gunk in the TB. The more the pressure buildup, the more gunk is deposited. For emissions reasons, the epa wants the engine to puke into the TB, not to the atmosphere thru a breather.
 
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Discussion Starter · #6 ·
OK so the passenger side is the one that makes the most gunk buildup? It's ok to replace with push on breather right?

Yesterday I traced the pcv valve tubing and it runs to the front of the block above the water pump. So I can't put a breather there?

So with pcv system is the valve closed at WOT or open?

Just trying to understand my motor more and more, you guys are a big help.
 
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Discussion Starter · #8 ·
<BLOCKQUOTE>quote:</font><HR>Originally posted by Bullyveldt:
OK so the passenger side is the one that makes the most gunk buildup? It's ok to replace with push on breather right?<HR></BLOCKQUOTE>

It's ok, but for a little gunk after 100,000 miles, is to me, not an overwhelming reason to add the breather. A little residue is normal, alot indicates a sealing problem in engine.

Yesterday I traced the pcv valve tubing and it runs to the front of the block above the water pump. So I can't put a breather there?

That is the source of the vacuum for the pcv valve. Are you attempting to defeat the funtion of the valve?

So with pcv system is the valve closed at WOT or open?

The valve is a one way check valve. It allows vacuum, but closes to prevent pressure surges from increasing the capacity of the oil pan.
So, under normal conditions, it is an open system. However, the strength of the vacuum signal will vary under different operating load conditions of the engine. Under a non presserized intake system (without FI) you will normally not see a pressure condition from idle to wot.
 
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Discussion Starter · #9 ·
Don't do it. The PCV system was one of the industy's better inventions. It keeps the crankcase purged of sludge forming gases the vast majority of running time. Before PCV systems, cars would sludge up terribly. - Jim
 
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Discussion Starter · #10 ·
can the air injection pump be used to vent out the gasses instead if the motor vacuum? you would have to re-route the hoses, and rewire the pump to run all the time. I dont know if the pump has enough suction to pump out the gasses
anyone tried it?
 
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Discussion Starter · #11 ·
the only reason you have sludge is lack of oil changes and a plugged pcv valve.

I'd vote no on the breather too.

change the oil every 3k and the valve at recommended intervals and your sludge will go away. well the majority of it will.

the pcv system is designed to put the crankcase in a vacuum under idle cruise by intake manifold vacuum.

under wot, there is no vacuum. the rush of air going thru the manifold causes the valve to close and, by way of venturi principle, the gases flow backward into the manifold.
 
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Discussion Starter · #12 ·
you could always run an evactuation system that moroso sells, you put 2 breathers in the valvecovers, and 2 check valves in the collectors or right after your shorties or manifolds, and then you run hoses from the valve cover to the check valves. It uses the exhaust to pull the excess pressure. This is what we run on our pro stock car.

If your ever at the drags, look at alot of the rail cars (bracket race dragsters) almost all of them run a simular system.

just another idea.
 
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Discussion Starter · #13 ·
Originally posted by Jons4door:
you could always run an evactuation system that moroso sells, you put 2 breathers in the valvecovers, and 2 check valves in the collectors or right after your shorties or manifolds, and then you run hoses from the valve cover to the check valves. It uses the exhaust to pull the excess pressure. This is what we run on our pro stock car.

If your ever at the drags, look at alot of the rail cars (bracket race dragsters) almost all of them run a simular system.

just another idea.
that would only work on an open header. street cars have too much back pressure to get a good vacuum signal in the collector
 
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Discussion Starter · #14 ·
we do run mufflers and piping after the header but there is basicly zero back pressure like you mentioned, it is dual 3" all the way out..
 
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