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Cobra Brake66 Install on 86 GT

  • Thread starter Thread starter Redfire 05
  • Start date Start date Jul 9, 2006

Redfire 05

New Member
Apr 6, 2005
236
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0
Lubbock, TX
Jul 9, 2006
#1
  • Jul 9, 2006
  • #1
I am 2/3rd's finished installing SN95 Cobra Brakes on my 86 GT, but I've run into a problem with the proportioning valve and master cylinder.

First, according to ford it is absolutely neccessary that you install the correct plug w/o hole in the end of the proportioning valve. The stock plug has a hole for the plunger. Problem is the plug ford sells doesn't fit the 86 prop valve. Is there another plug you can use? Those who have done this swap what did you do?

Second the brake lines on my 86 have SAE threads and the 94 up master cylinders are metric. I'm thinking of using the 85 towncar mc instead so I don't have to cut and flare the lines. Or alternativly does someone know the adapters you need to fit the lines to the new mc?
 

trbkrb

Founding Member
Jun 4, 2001
1,976
4
39
Houston, TX
Jul 9, 2006
#2
  • Jul 9, 2006
  • #2
You might PM Joe, stang&2Birds on here and see what he did. He has a 86 GT with the M2300K kit on it.

Good luck!
 

stang&2Birds

Founding Member
May 4, 2000
2,091
5
58
New England. :-) CT/MA
Jul 9, 2006
#3
  • Jul 9, 2006
  • #3
I just double checked. I used the prop valve and plug that came with the M2300K kit. I have new brake lines that go from the MC to the prop valve. I don't think that I did any ISO flares. Maybe they sell ISO brake lines that have the correct fittings on both sides? Sorry, I don't remember the details.
 

Redfire 05

New Member
Apr 6, 2005
236
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Lubbock, TX
Jul 9, 2006
#4
  • Jul 9, 2006
  • #4
Unfortunately I didn't buy the kit, I pieced it together. I suppose I could try to find a prop valve from an SN95 and see if it works. I know a few others have done this with their 86's what did ya'll do?
 

stang&2Birds

Founding Member
May 4, 2000
2,091
5
58
New England. :-) CT/MA
Jul 9, 2006
#5
  • Jul 9, 2006
  • #5
It should be some standard thread size. Take the plug to a local bolt/hardware store - maybe even Home Depot.

You just need to get a stainless steel bolt to plug the end (after you gut the prop valve). Or, you can have the end of the stock plug welded.

I think that a new prop valve goes for ~$75 to $175 - not cheap.
 

Redfire 05

New Member
Apr 6, 2005
236
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0
Lubbock, TX
Jul 9, 2006
#6
  • Jul 9, 2006
  • #6
stang&2Birds said:
It should be some standard thread size. Take the plug to a local bolt/hardware store - maybe even Home Depot.

You just need to get a stainless steel bolt to plug the end (after you gut the prop valve). Or, you can have the end of the stock plug welded.

I think that a new prop valve goes for ~$75 to $175 - not cheap.
Click to expand...

Yeah I thought about getting the end welded. That might be the easiest and cheapest.
 

Deece

Member
Sep 16, 2005
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0
7
Jul 9, 2006
#7
  • Jul 9, 2006
  • #7
The plug fit in my 86 just fine, no ide why yours wouldn't unless someone changed the pV? as for the brake lines I brought my hard lines from the MC to PV and MC into NAPA and got the right adapters took about 5 mins.
 

stang&2Birds

Founding Member
May 4, 2000
2,091
5
58
New England. :-) CT/MA
Jul 9, 2006
#8
  • Jul 9, 2006
  • #8
Deece said:
as for the brake lines I brought my hard lines from the MC to PV and MC into NAPA and got the right adapters took about 5 mins.
Click to expand...
They have SAE to ISO adapters? I didn't think they made those. I did mine a while back. So, I wouldn't be surprised if they have a lot more adapters for ISO by now. Before, I couldn't even get any ISO to ISO size adapters.
 

Redfire 05

New Member
Apr 6, 2005
236
0
0
Lubbock, TX
Jul 10, 2006
#9
  • Jul 10, 2006
  • #9
Okay so it turns out the plug did actually fit. I tried it again today. Apparantly lots of cold medicine and little sleep makes seemingly simple tasks like screwing a bolt in a hole very difficult.
 
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