Which master cylinder?

[ClayBelt]

I've got a 1986 SVO I just put a new brake booster in and am getting ready to put 03-04 Cobra front brakes on (via 95 spindles). I was told the 1 1/8" master cylinder will be too stiff, especially with braided stainless lines. Given that I would like to retain my stock booster if possible, what master cylinder should I use?

 

[Mustang5L5]

Try the 85 Town car 1” MC. It should be a direct bolt on for the SVO as they both use SAE thread pitch fittings.

The SN95 MCs are a little bit of a PITA to plumb is as they are metric thread so you will need to cut and flare

 

[ClayBelt]

So a 1” bore MC should give me an adequately firm brake pedal with the 40mm twin piston cobra calipers up front and 54mm SVO rear calipers? I do want it to be a little firm, just not too firm to use.

 

[Mustang5L5]

Let me run the numbers in the AM. I have some data on my PC on MC ratio calcs.

 

[ClayBelt]

Awesome man

 

[Mustang5L5]

SVO calipers are 8370mm^2 of piston surface area. 99-04 CObra calipers are 5152mm^2. Rear calipers are 4580mm^2 and remain constant.

SO swapping the SVO fronts to the cobra calipers is a 25% reduction in total surface area of all the calipers.

1 1/8" SVO is 638mm^2 of area. The 1" bore MC is 507mm^2. That;s a 20% reduction. That's as close as you are going to get.

1993 cobra, and 85 lincoln town car both have 1" bore MC's, but the town car MC will be an easier swap since it's SAE threads. However, the SVO MC might need an adapter since it appears one line is a different pitch. You might need to swap it with a standard GT line. Unfortunately i don't know this info completely, so you might have to do some legwork

1986 SVO master cylinder vs Lincoln master cylinder

Hey guys you've helped me tremendously in the past and hope you can help me again. Basically I'm doing the 11" brake upgrade with the 73mm lincoln/svo calipers. I'm gathering all the parts and I've read the Matt GT web page a million times. Here is my question: on the web page it says all...

vb.foureyedpride.com

 

[ClayBelt]

I managed to get ahold of some SVO owners who were running this style setup early this morning actually, seems a lot of them are continuing to use the SVO master cylinder. If that one feels too stiff for me though when I do my swap I’ll try the town car one.