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PCV Removal?

Sekred

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#2
Hi rx7

Myself, I would not remove the PCV valve from the system unless you decided to turn your ST into a dedicated Track car where your basically driving flat out or parked. Lots of throttle and lots of boost is going to produce more blow by.
As you would know, when the PCV valve opens crankcase fumes are draw into the inlet manifold, also fresh filtered air flows into the crankcase through the other hose connected between the valve cover and the inlet tube. This flow of fresh air helps to purge moisture and other crap from the crankcase as the engine comes up to operating temp from a cold start.
Removal of the pcv valve and going to open vented system can cause sludging of the oil because the condensation does not burn off properly.
I would just go with a catch can in the OEM system.
 


OP
re-rx7

re-rx7

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Thread Starter #3
Hi rx7

Myself, I would not remove the PCV valve from the system unless you decided to turn your ST into a dedicated Track car where your basically driving flat out or parked. Lots of throttle and lots of boost is going to produce more blow by.
As you would know, when the PCV valve opens crankcase fumes are draw into the inlet manifold, also fresh filtered air flows into the crankcase through the other hose connected between the valve cover and the inlet tube. This flow of fresh air helps to purge moisture and other crap from the crankcase as the engine comes up to operating temp from a cold start.
Removal of the pcv valve and going to open vented system can cause sludging of the oil because the condensation does not burn off properly.
I would just go with a catch can in the OEM system.
I have to disagree, respectfully. The secondary tube also (under boost) vents Crankcase Pressure into the intake tract. Under boost the PCV shuts to keep boost from entering the CrankC. Since Im running VTA I do not have the Vaccuum from the IM to pull Vapors from the CC under normal driving. So by removing the inards of the PCV allows the blowby to exit unhinhibited. The secondary will always be pulling fresh air from the intake either way.
 


felopr

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#4
I have to disagree, respectfully. The secondary tube also (under boost) vents Crankcase Pressure into the intake tract. Under boost the PCV shuts to keep boost from entering the CrankC. Since Im running VTA I do not have the Vaccuum from the IM to pull Vapors from the CC under normal driving. So by removing the inards of the PCV allows the blowby to exit unhinhibited. The secondary will always be pulling fresh air from the intake either way.
I was going to say the same thing as sekred, but since you put it that way, that you have a VTA catch can, it would make more sense to remove the pcv valve.
i was looking at some parts catalog but i can really find the pcv valve location, maybe is integrated to the IM?
 


Sekred

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#5
I have to disagree, respectfully. The secondary tube also (under boost) vents Crankcase Pressure into the intake tract. Under boost the PCV shuts to keep boost from entering the CrankC. Since Im running VTA I do not have the Vaccuum from the IM to pull Vapors from the CC under normal driving. So by removing the inards of the PCV allows the blowby to exit unhinhibited. The secondary will always be pulling fresh air from the intake either way.
I aware how the system works when the engine is boosting or producing manifold vacuum. A VTA won't purge crankcase gases as well as a PCV system.

Here a link to the focusfanatics forum showing how one member deleted the PCV valve.

http://www.focusfanatics.com/forum/showthread.php?t=361177
 


OP
re-rx7

re-rx7

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Thread Starter #6
Thanks for the link. Wow their pcv is a whore to get at. Lol
 


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