proportioning valve

Discussion in 'Technical' started by bomrat, Jan 20, 2015.

  1. bomrat

    bomrat Member

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    hi, I had disc / drum setup on my car.. I installed rear discs. I am noticing that it is pretty soft stop, feels like I need more front brake, or less rear. pedal is firm but I really have to mash on it to stop and still have plenty of pedal travel to go. I had ss braided lines made up for front and rear, so no rubber lines left. do I need to change the proportioning valve? if so what should I go to?
    thanks
     
    bomrat, Jan 20, 2015
    #1
  2. rthomas771

    rthomas771 Member

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    I'm still using the disc/drum master with 4-wheel disc and no issues. I have '96 Grand Marquis disc on the rear and Maverick disc up front.
     
    rthomas771, Jan 20, 2015
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  3. 71gold

    71gold Frank Cooper Supporting Member

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    sounds like air in the lines...:yup:

    I ran the disc/drum master with 4-wheel disc and no issues.
     
    71gold, Jan 22, 2015
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  4. Krazy Comet

    Krazy Comet Tom

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    Too much rear brake bias will cause rear lockup before the front under moderate to hard braking... Without enough rear braking, car will feel like it doesn't want to stop even with fronts at point of lockup...
     
    Krazy Comet, Jan 22, 2015
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  5. Rasit

    Rasit Member

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    I would. If you do a search on this here you will find many differing opinions. There are distinct differences in the different proportioning valves and how they effect the rear brake bias. A disc/drum valve maintains residual pressure to the rear is one difference. You're going to have to do some research and decide for yourself. Personally when I switched from drum/drum to disk/drum, I made sure everything matched for the brake system I was going with which meant changing both the master cylinder and the proportioning valve.
     
    Last edited: Jan 22, 2015
    Rasit, Jan 22, 2015
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  6. 71gold

    71gold Frank Cooper Supporting Member

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    my setup now has no prop. valve. the larger tires on the back are the bias.
     
    71gold, Jan 23, 2015
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  7. Rasit

    Rasit Member

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    Fred and Barney would just use their feet....
     
    Rasit, Jan 23, 2015
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