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Old 03-14-2017, 09:24 AM   #1
whiterabbitrexy
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Default pcv vta.... can it be done correct ?

As stated can the pcv be vta with a good easy setup ? i dont want hot oily fumes back into my intake/combustion chamber?

Ive read heaps of forum on diffrent setups but almost always towords the end the the forum there is no real facts that it works except one setup with a electric vaccum motor that pulls pcv fumes out .... but i could never find that pump was hopeing someone could point me in the right direction
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Old 03-14-2017, 09:28 AM   #2
Jack
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Uh, just run a hose under the car like my old 51 Ford F2 with a flathead V8 had. Leave that signature oil slick down the middle of the road like you see in old movies. Or run the hose into a 1L Polar grape seltzer bottle so you don't pollute the whole world. You don't need a pump. The oil vapor is only going to come out under its own pressure.
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Old 03-14-2017, 09:34 AM   #3
whiterabbitrexy
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Quote:
Originally Posted by Jack View Post
Uh, just run a hose under the car like my old 51 Ford F2 with a flathead V8 had. Leave that signature oil slick down the middle of the road like you see in old movies. Or run the hose into a 1L Polar grape seltzer bottle so you don't pollute the whole world. You don't need a pump. The oil vapor is only going to come out under its own pressure.
not completly true... if left to vta there still is some pressure in the crank case that needs to be sucked out to help with the engine to spine freely....

but thanks for the tip jack wish it was that easy

Oh crap how do i delete a thred
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Old 03-14-2017, 01:46 PM   #4
Charlie-III
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Reality is you get the majority of fumes "cheap", to be perfect that last little bit can get expensive.
My bet would be a AOS followed by an oil vapor filter (industrial compressed air part, likely $300 and up for a big enough flow rate) before getting back to the intake. You can look on WWGraingers for some oil vapor filters in the compressed air section. They are commonly used on oil seal twin screw air compressors.

Between the 2 parts, time installing, having room is it worth maybe $800+ to not have to do some cleaning? Your call. Yes, I understand the thought that oil vapor in the intake can lower octane.

Crap, vta is Vent To Atmosphere, I was thinking plumbing back into the intake. Not sure what I would use as a pump. A vane pump might work, but not sure how the vanes would deal with the oil vapors. Maintenance would likely be high, under 10K miles?

You want to apply a light vacuum to the crankcase which can reduce pumping losses as well as remove oil vapors, correct?

.

Last edited by Charlie-III; 03-14-2017 at 01:54 PM.
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Old 03-14-2017, 02:14 PM   #5
A-man07
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Hard to get a vacuum on an open system such as with a VTA can. Better to use a catch can and just drain it however often it needs.
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Old 03-15-2017, 07:09 AM   #6
whiterabbitrexy
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Quote:
Originally Posted by Charlie-III View Post
Reality is you get the majority of fumes "cheap", to be perfect that last little bit can get expensive.


You want to apply a light vacuum to the crankcase which can reduce pumping losses as well as remove oil vapors, correct?

.
yeah correct i want to pull vaccum from the crankcase and completly vta oil vapor hot air...

yeah only want to cool down the air going into the combustion chamber so thats why i was thinking of vta the pcv ..... now since i cant vta because of possitive pressure left in the engine block and its very hard to pull vaccum out with not hooking it up to the turbo inlet was thinking about somthing else to do

has any one installed a catch can at the front of the bumper bar in the foglight area ? was thinking of installing it behind the foglight to get cold air to cool down the catch can to cool down the hot pcv air going through to the catch can.... but i doubt its going to do much cooling ....still want to vta pcv completly
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Old 03-15-2017, 11:41 AM   #7
Stew3223
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Quote:
Originally Posted by whiterabbitrexy View Post
yeah correct i want to pull vaccum from the crankcase and completly vta oil vapor hot air...

..... now since i cant vta because of possitive pressure left in the engine block and its very hard to pull vaccum out with not hooking it up to the turbo inlet was thinking about somthing else to do

....still want to vta pcv completly
Where to begin? This is one of these topics that all the armchair engineers like to spout off about without any real knowledge.

Even with a PCV system there will still usually be a small pressure inside the crankcase. This is completely normal.

It is impossible to "completely" vent the crankcase of oil vapor because much of it will remain in the crankcase and settle back into the oil pan. And that's okay...because its oil vapor. It will contain some level of unburned hydrocarbons but not at any significant level that would have any negative impact.

There is, in my opinion, no measurable advantage of a PCV system on performance or pumping losses or friction. It is quite simply an emissions control system.

If you're concerned about PCV vapor entering the intake, dump all the vents into a catch can and empty it periodically. Done!
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Old 03-15-2017, 10:30 PM   #8
whiterabbitrexy
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Quote:
Originally Posted by Stew3223 View Post
Where to begin? This is one of these topics that all the armchair engineers like to spout off about without any real knowledge.

Even with a PCV system there will still usually be a small pressure inside the crankcase. This is completely normal.

It is impossible to "completely" vent the crankcase of oil vapor because much of it will remain in the crankcase and settle back into the oil pan. And that's okay...because its oil vapor. It will contain some level of unburned hydrocarbons but not at any significant level that would have any negative impact.

There is, in my opinion, no measurable advantage of a PCV system on performance or pumping losses or friction. It is quite simply an emissions control system.

If you're concerned about PCV vapor entering the intake, dump all the vents into a catch can and empty it periodically. Done!

very true what u said

but a honest question to you stew3223 ...... have you put your finger over a open hose of a pvc when engine is at wot ..... so pulling the throttel cable and puting your finger over the pcv hose??
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