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Engine Help A Dummy Out! Pcv Valve Plumbing Question

  • Thread starter Thread starter Husky44
  • Start date Start date Mar 27, 2014

Husky44

10 Year Member
Sep 27, 2006
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104
74
Tacoma, WA
Mar 27, 2014
#1
  • Mar 27, 2014
  • #1
In a hurry to finish the build of my 67 convertible restomod for the 50th in Charlotte. Running a 5.0 from a 91 LX, with TF intake, heads, no EGR system, no smog anything.

I have the PCV valve installed in the back of the lower intake. There's two connections on the valve. Where do they connect to? I would guess one of the two feeds into the air intake somewhere, but not sure where. Is this what connects to the fitting on top of the throttle body?

I know search would probably reveal my answer, but that takes away from wrench time, and somebody on here will know this off the top of their head. Besides, it gives you the opportunity to beat me up for not searching!

Seriously, thanks for the help!
 

kpack5982

Yeah, it was pretty stiff, but eventually a buddy
Jul 13, 2005
325
1
19
Granger, IA
Mar 27, 2014
#2
  • Mar 27, 2014
  • #2
Block one of them off and the other one goes to a vacuum source on the intake manifold
 

Grabbin' Asphalt

10 Year Member
Jun 10, 2013
2,029
310
124
Atlanta, Ga
Mar 27, 2014
#3
  • Mar 27, 2014
  • #3
Either feed them both to the Intake, one in the middle of Intake and the other to the open end(if its open) on the bottom edge ports on the driver(under side part of intake). If they are plugged then do the suggestion above.
 

89oem

Mustang Master
Dec 18, 2013
1,456
542
144
Mar 27, 2014
#4
  • Mar 27, 2014
  • #4
the throttle body nipple connects to the nipple on the valve cover filler neck
 

Husky44

10 Year Member
Sep 27, 2006
865
104
74
Tacoma, WA
Mar 29, 2014
#5
  • Mar 29, 2014
  • #5
89oem said:
the throttle body nipple connects to the nipple on the valve cover filler neck
Click to expand...

Dumb question #2: What does this do? I don't have a filler cap or neck yet for my car (running TF valve covers), but why would I want atmospheric pressure air from inside the valve cover feeding into my throttle body? Is this an emissions control function of some sort? Wouldn't it make more sense to plug the nipple on the throttle body, instead of introducing oily air from the valve cover?
 

RacEoHolic330

I like to dress like a pretty girl
15 Year Member
Mar 4, 2003
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203
Allentown, PA
Mar 29, 2014
#6
  • Mar 29, 2014
  • #6
The crankcase needs to breathe. It's a push-pull type of system. It needs a fresh air source after the MAF meter that is not under boost or vacuum. You won't have to worry about it introducing any oil into the throttle body.
 
Reactions: Grabbin' Asphalt

Husky44

10 Year Member
Sep 27, 2006
865
104
74
Tacoma, WA
Mar 29, 2014
#7
  • Mar 29, 2014
  • #7
RacEoHolic330 said:
The crankcase needs to breathe. It's a push-pull type of system. It needs a fresh air source after the MAF meter that is not under boost or vacuum. You won't have to worry about it introducing any oil into the throttle body.
Click to expand...
Thanks for the quick reply. Was looking to simplify wherever possible; but at the same time I need to get this done in less than 2 weeks, so I don't want to introduce more problems by modifying where not necessary.
 
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