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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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block off pcv valve?

  • Thread starter Thread starter Bad92GT
  • Start date Start date Jun 19, 2006

Bad92GT

The 5 Minute Plan Man
Jun 10, 2004
492
0
0
SC
Jun 19, 2006
#1
  • Jun 19, 2006
  • #1
can i just "block" the bastard off? what does it do exactly? relieve pressure in the crank case correct? im catchin hell with filters and all when i try and set up a pcv filter system.. any help?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jun 19, 2006
#2
  • Jun 19, 2006
  • #2
Post specifics about what you have and what you desire. Running PCV and breathers simultaneously is not a great idea (you have unmetered air issues).

The crankcase ventillation equalizes crankcase pressure - it's flow is bi-directional.

Good luck.
 

Bad92GT

The 5 Minute Plan Man
Jun 10, 2004
492
0
0
SC
Jun 19, 2006
#3
  • Jun 19, 2006
  • #3
well i have.. thumpers, typhoon intake *which doesnt use the lil screen*, 2021 crane cam.. (high lift).. its a street/track car.. i daily drive it everyday.. and i installed a filter system between the pcv hoses and instead of getting rid of blowby or oil coming up and getting into the intake, it just sucked the oil out the filter under hard vaccum.. 4th gear and you get on it a bit.. throttles open more than the rpms are turning.. making tons of vaccum
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jun 19, 2006
#4
  • Jun 19, 2006
  • #4
manifold vacuum is inversely proportionate to how far the throttle is open per delta-time.

E.g., at WOT, there's almost no vacuum.

But at WOT, there's the most crankcase pressure - that will test the flowing ability of your crankcase ventillation. The screen/baffle for the intake helps a lot.

Do you use a fuel filter type of inline filter, or a separator? The trap in the separator helps keep oil from being scavenged and recirculated at WOT.
 

89Notch

Founding Member
Oct 21, 1999
1,669
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0
MSU
Jun 19, 2006
#5
  • Jun 19, 2006
  • #5
Have a breather on one side and on the other a line to the vacuum tree with an inline oil/air separator...
 
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