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

Brake swap

  • Thread starter Thread starter Ybfav84
  • Start date Start date Feb 22, 2025
  • Tags Tags
    5.0 brake brake conversion four eye foxbody 5.0
Y

Ybfav84

Member
Dec 1, 2024
30
5
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California
Feb 22, 2025
#1
  • Feb 22, 2025
  • #1
So I’m almost done with my brakes
Do I have to gut the proportioning valve?
And can I run my brakes without one?
Also I was pumping my brakes and no fluid is going down
What could be the issue?
 

KRUISR

10 Year Member
Apr 16, 2015
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Feb 22, 2025
#2
  • Feb 22, 2025
  • #2
A few more details are needed. What swap are you doing? From what system to what system? What have you changed?
 
Y

Ybfav84

Member
Dec 1, 2024
30
5
18
California
Feb 22, 2025
#3
  • Feb 22, 2025
  • #3
KRUISR said:
A few more details are needed. What swap are you doing? From what system to what system? What have you changed?
Click to expand...
My bad feeling stressed with all this lol it’s a 1984 mustang 5.0
1993 mc
1993 booster
95GT rear end and brakes
Front 04 cobra brakes
 

nickyb

I gotta say i never painted my nuts, Never Ever
15 Year Member
Apr 3, 2009
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Feb 22, 2025
#4
  • Feb 22, 2025
  • #4
Yeah you have to either gut the p valve and run an adjustable one or as I did replace the guts with 94 or 95 innards.
 
Reactions: General karthief
Y

Ybfav84

Member
Dec 1, 2024
30
5
18
California
Feb 22, 2025
#5
  • Feb 22, 2025
  • #5
nickyb said:
Yeah you have to either gut the p valve and run an adjustable one or as I did replace the guts with 94 or 95 innards.
Click to expand...
I see
Any idea of where I can buy the guts?
 

nickyb

I gotta say i never painted my nuts, Never Ever
15 Year Member
Apr 3, 2009
2,972
1,618
153
nevada
Feb 22, 2025
#6
  • Feb 22, 2025
  • #6
I got mine from a pic a part ,1995 gt.
 
Reactions: Ybfav84 and General karthief

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,797
3,930
183
Claremore, OK
Feb 23, 2025
#7
  • Feb 23, 2025
  • #7
Just got it and install a manual proportioning valve.

OEM combination valve plug:

Brake Proportioning Valve Plug, 1979-2004

www.maximummotorsports.com

Manual proportioning valve:
Adjustable Brake Proportioning Valve, SAE ports

This will allow you to dial the brakes in. Both my cars are done this way and both are a little different on the rear brake bias but stop like a champ.
 
Reactions: General karthief
Y

Ybfav84

Member
Dec 1, 2024
30
5
18
California
Feb 23, 2025
#8
  • Feb 23, 2025
  • #8
AeroCoupe said:
Just got it and install a manual proportioning valve.

OEM combination valve plug:

Brake Proportioning Valve Plug, 1979-2004

www.maximummotorsports.com

Manual proportioning valve:
Adjustable Brake Proportioning Valve, SAE ports

This will allow you to dial the brakes in. Both my cars are done this way and both are a little different on the rear brake bias but stop like a champ.
Click to expand...
I appreciate the help
Is that the reason no brake fluid travels down the mc when I press on the brakes?
 

85GTStangGuy

5 Year Member
May 19, 2021
998
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Jax, Florida
Feb 23, 2025
#9
  • Feb 23, 2025
  • #9
Did you bench bleed the mc?
 
Y

Ybfav84

Member
Dec 1, 2024
30
5
18
California
Feb 23, 2025
#10
  • Feb 23, 2025
  • #10
85GTStangGuy said:
Did you bench bleed the mc?
Click to expand...
I bought it used, I didn’t smh
 

limp

wrap a little cheese around it and its a done
5 Year Member
Oct 4, 2020
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Feb 23, 2025
#11
  • Feb 23, 2025
  • #11
Ybfav84 said:
I bought it used, I didn’t smh
Click to expand...
So you don't even know if the MC works> The seals go out in them... They might look perfect if you take it apart, but they can still be bad....
 
Y

Ybfav84

Member
Dec 1, 2024
30
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18
California
Feb 23, 2025
#12
  • Feb 23, 2025
  • #12
the guy said he didn’t use it
Ig he tried it but ended up going another route
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,797
3,930
183
Claremore, OK
Feb 23, 2025
#13
  • Feb 23, 2025
  • #13
Pull it and bench bleed.
 
Reactions: General karthief
Y

Ybfav84

Member
Dec 1, 2024
30
5
18
California
Feb 23, 2025
#14
  • Feb 23, 2025
  • #14
AeroCoupe said:
Pull it and bench bleed.
Click to expand...
Will do Tomorrow
 

Habu135

5 Year Member
Jan 10, 2019
1,217
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California
Feb 27, 2025
#15
  • Feb 27, 2025
  • #15
You might consider doing a search on this topic here. It's a well worn path.
 
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