Brake issues 2Ton Viking 59

[Softpatch]

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.http://67-72chevytrucks.com/vboard/s...d.php?t=770501
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Reading this thread and doing more home work will open more question with no answer need some guidance
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I suffer from pedal bleed down
when I let off the pedal the fluid violently return back to master
Residual valve .?
is this not built into the master cylinder.?

My system is stock (one resivor) and the bore is 1.1/4
could I use a 1. bore just know it would take more pedal.?
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I have been fighting this for many years
don't know where im going with my truck
what i do not want to do is change the originalatly of the truck
the original brakes might have to be sacificed for over all driveability
would pitch the Hydrovac and 1.1/4 bore signal master cylinder for a 7" vacuum booster double master Like this
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any feed back to get my dad's truck back on the road would be much apreciated Thanks ...SP
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Hydrovac and 1.1/4 bore master cylinder
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