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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Blocking Off PCV

  • Thread starter Thread starter ATISTANG
  • Start date Start date Mar 27, 2009

ATISTANG

Member
Apr 15, 2006
104
0
16
Mar 27, 2009
#1
  • Mar 27, 2009
  • #1
What is the best and easiest way to block off the PCV port on the back of the intake manifold?

I'm gonna run breathers and do away with the pcv valve
 

90lxcoupe

20+ Year Stangneter
Oct 7, 2003
3,596
350
134
Mar 27, 2009
#2
  • Mar 27, 2009
  • #2
I machined an aluminum plug and pressed it into the back of the intake. Careful running breathers in the VC though, they WILL fall out under hard acceleration and can cause a fire if you dont catch the problem.

The right way to do it is to run -AN fittings off the valvecover to a breather tank. NA you can get away with one fitting but boosted you are going to need a -12an fitting on each valve cover
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Mar 27, 2009
#3
  • Mar 27, 2009
  • #3
Cram a breather in the pcv port....
 

Strype

Cuthbert catcher
Founding Member
May 11, 1999
61
34
104
Huntsvegas, AL
Mar 27, 2009
#4
  • Mar 27, 2009
  • #4
I just capped the tube
 

ATISTANG

Member
Apr 15, 2006
104
0
16
Mar 28, 2009
#5
  • Mar 28, 2009
  • #5
90lxcoupe said:
I machined an aluminum plug and pressed it into the back of the intake. Careful running breathers in the VC though, they WILL fall out under hard acceleration and can cause a fire if you dont catch the problem.

The right way to do it is to run -AN fittings off the valvecover to a breather tank. NA you can get away with one fitting but boosted you are going to need a -12an fitting on each valve cover
Click to expand...
I have trick flow valve covers with the filler neck they provide with it, i'm going to put a breaker in place of the cap, then i was gonna do the same on the opposite side

how would i attach an an fitting to the valve cover? i don't have much room for anything hanging down from the valve cover without hitting the rockers.

also i thought someone sold plugs for the pcv port?

Strype said:
I just capped the tube
Click to expand...
my valve keeps popping out of the intake, so thats not gonna help
 
G

greg251

New Member
Dec 17, 2006
55
0
0
Mar 28, 2009
#6
  • Mar 28, 2009
  • #6
Rubber freeze out plug works best.
 

KamiKaziDK

Member
May 16, 2005
555
0
17
Mesa, Az
Mar 28, 2009
#7
  • Mar 28, 2009
  • #7
greg251 said:
Rubber freeze out plug works best.
Click to expand...

 

blackened88lx

Active Member
Aug 9, 2006
0
4
28
Connecticut
Mar 29, 2009
#8
  • Mar 29, 2009
  • #8
ATISTANG said:
how would i attach an an fitting to the valve cover? i don't have much room for anything hanging down from the valve cover without hitting the rockers.
Click to expand...

It will not go into the valve cover at all. Just buy the fittings, figure out what would be the most convenient place to mount them on your valve covers, mark, and drill a hole. Bring them to someone with a tig welder and have the fittings welded onto the valve covers. Then run some hose to a catch can with a breather on it. Oh, and obviously do the drilling and welding with the valve covers off the car...

Or if you don't want to weld on your valve covers and have to repaint them, you might be able to try drilling and tapping them and threading the fittings in with some sealant for a cleaner look.

This is a picture of the setup.
 

ATISTANG

Member
Apr 15, 2006
104
0
16
Mar 30, 2009
#9
  • Mar 30, 2009
  • #9
greg251 said:
Rubber freeze out plug works best.
Click to expand...

KamiKaziDK said:
Click to expand...
what size? and did you just drive it in, or did you use some rtv around it or anything?
blackened88lx said:
It will not go into the valve cover at all. Just buy the fittings, figure out what would be the most convenient place to mount them on your valve covers, mark, and drill a hole. Bring them to someone with a tig welder and have the fittings welded onto the valve covers. Then run some hose to a catch can with a breather on it. Oh, and obviously do the drilling and welding with the valve covers off the car...

Or if you don't want to weld on your valve covers and have to repaint them, you might be able to try drilling and tapping them and threading the fittings in with some sealant for a cleaner look.

This is a picture of the setup.
Click to expand...
I think I'm gonna go with the breather in the end of the filler neck, i know a guy going this route and doesn't have any problems. Right now all it has to breath through is a 1/4 inch pipe fitting with a hose on it, until it pops the pcv valve out that is lol.

if that doesn't work then i'll already have a hole in each valve cover so i can go with the AN fitting and catch can setup
 

95Vert383AOD

15 Year Member
Jun 10, 2008
1,133
34
69
New Bedford, MA
Mar 30, 2009
#10
  • Mar 30, 2009
  • #10
Why do this? Don't we want the pressure relieved? Problems like Valve cover gaskets or intake oil valley gaskets losing seal and losing oil can will happen. What is the benefit to this MOD other than Gases & Temp. buildup? I toss this mod in the box along with removing the vacuum line off your fuel pressure regulator. But thats just me....

I run 1 PCV and 2 breathers (one on each valve cover) piped to the intake before the TB.
Venting the Crank case up threw the push rod holes of the head and threw the valve cover isn't the most efficient way of doing this. I'm pretty sure your crankcase temps will increase threw this "MOD"

With that said i have had oil control issues using a PCV if you do and this is a reason for your mod then your problem lies elsewhere. I have ZERO oil being sucked into my intake...a PCV will not hinder performance.
 

ATISTANG

Member
Apr 15, 2006
104
0
16
Mar 30, 2009
#11
  • Mar 30, 2009
  • #11
95Vert383AOD said:
Why do this? Don't we want the pressure relieved? Problems like Valve cover gaskets or intake oil valley gaskets losing seal and losing oil can will happen. What is the benefit to this MOD other than Gases & Temp. buildup? I toss this mod in the box along with removing the vacuum line off your fuel pressure regulator. But thats just me....

I run 1 PCV and 2 breathers (one on each valve cover) piped to the intake before the TB.
Venting the Crank case up threw the push rod holes of the head and threw the valve cover isn't the most efficient way of doing this. I'm pretty sure your crankcase temps will increase threw this "MOD"

With that said i have had oil control issues using a PCV if you do and this is a reason for your mod then your problem lies elsewhere. I have ZERO oil being sucked into my intake...a PCV will not hinder performance.
Click to expand...

I think it will be fine, i have seen many renegade cars set up this way

i'm not sucking any oil as with boost i don't want to plum the pcv to the TB, under hard accel it will pump boost into the crank case and or just slam the pcv shut
 

blackened88lx

Active Member
Aug 9, 2006
0
4
28
Connecticut
Mar 30, 2009
#12
  • Mar 30, 2009
  • #12
ATISTANG said:
I think I'm gonna go with the breather in the end of the filler neck, i know a guy going this route and doesn't have any problems. Right now all it has to breath through is a 1/4 inch pipe fitting with a hose on it, until it pops the pcv valve out that is lol.

if that doesn't work then i'll already have a hole in each valve cover so i can go with the AN fitting and catch can setup
Click to expand...

My buddy ran that setup for a little while with the breather in the filler neck. It was ok but it blew oil all over the engine bay every time he beat on it. Then we just came up with the hose setup.

95Vert383AOD said:
Why do this? Don't we want the pressure relieved? Problems like Valve cover gaskets or intake oil valley gaskets losing seal and losing oil can will happen. What is the benefit to this MOD other than Gases & Temp. buildup? I toss this mod in the box along with removing the vacuum line off your fuel pressure regulator. But thats just me....

I run 1 PCV and 2 breathers (one on each valve cover) piped to the intake before the TB.
Venting the Crank case up threw the push rod holes of the head and threw the valve cover isn't the most efficient way of doing this. I'm pretty sure your crankcase temps will increase threw this "MOD"

With that said i have had oil control issues using a PCV if you do and this is a reason for your mod then your problem lies elsewhere. I have ZERO oil being sucked into my intake...a PCV will not hinder performance.
Click to expand...

Nah, it works mint. Boosted cars blow the pcv valve out of the intake because it doesn't vent well enough. This setup has and will fix all problems. There's a reason everyone with a real blower/turbo car runs this or a similar setup.
 

kendoo130

Founding Member
May 30, 2002
244
0
16
Huntington Station N.Y.
Mar 30, 2009
#13
  • Mar 30, 2009
  • #13
vristang said:
Cram a breather in the pcv port....
Click to expand...

I did this also-I put a small K&N breather on there. I also run valve cover breathers.
 

95Vert383AOD

15 Year Member
Jun 10, 2008
1,133
34
69
New Bedford, MA
Mar 31, 2009
#14
  • Mar 31, 2009
  • #14
OOOOOh now i understand. Thanks just never knew why folks set it up this way. I noticed my friends 98 Lincoln mark viii doesn't have a PCV on the crank case. It has one on each valve cover.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Apr 5, 2009
#15
  • Apr 5, 2009
  • #15
95Vert383AOD said:
Why do this? Don't we want the pressure relieved? Problems like Valve cover gaskets or intake oil valley gaskets losing seal and losing oil can will happen. What is the benefit to this MOD other than Gases & Temp. buildup? I toss this mod in the box along with removing the vacuum line off your fuel pressure regulator. But thats just me....

I run 1 PCV and 2 breathers (one on each valve cover) piped to the intake before the TB.
Venting the Crank case up threw the push rod holes of the head and threw the valve cover isn't the most efficient way of doing this. I'm pretty sure your crankcase temps will increase threw this "MOD"

With that said i have had oil control issues using a PCV if you do and this is a reason for your mod then your problem lies elsewhere. I have ZERO oil being sucked into my intake...a PCV will not hinder performance.
Click to expand...
If you are running breathers AND a pcv.... then you have created a vac leak via the breathers....
I'm sure it runs, but it isn't ideal.

2 General rules -
1. The more breathers the better, which is why I suggested installing a breather on the pcv port of the lower intake... INSTEAD of plugging/capping the hole off. (Obviously there is a point of diminishing return: 10 breathers probably won't gain much over 3 breathers)

2. Breathers and pcv's don't mix.
 

67coupe

Founding Member
Apr 5, 2002
658
402
93
Huntsville, AL
Apr 6, 2009
#16
  • Apr 6, 2009
  • #16
vristang said:
Cram a breather in the pcv port....
Click to expand...

I did this yesterday in an effort to reduce oil consumption. I used this from Autozone:

Spectre 3/4" i.d. push in breather. Part# 4300

It fit directly into the pcv port. Just be sure to plug the hole at the TB and the vacuum fitting on the manifold for the PCV valve. For me, it completely eliminated the cloud of blue smoke after periods of long idle.
 
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