68 newport not stopping as it should?

Brakes, Suspension, Rims and Tires

  1. CARL J KUSTREBA

    CARL J KUSTREBA New Member

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    hello all, having issues with my newport. it takes alot to stop the car. not sure whats going on. new master and booster, bled all lines, checked all brakes shoes and drums all look good. the only thing is low manifold vacuum, only showing 10 at idle. it does have an agressive cam, i know the power brakes need more. the car feels like manual drum brakes with no power assist. been searching and cant find anything. running out of ideas. car is a 68 with a built 383 and 4 wheel power drum brakes. thanks, carl
     
  2. 413

    413 Well-Known Member

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    Well you have found the problem, now fix it.

    The combination you put into a car must work together or you will be unhappy.

    A bad choice was made. Watcha gonna do for it now?
     
  3. CARL J KUSTREBA

    CARL J KUSTREBA New Member

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    hello, im thinking a vacuum canister to help out the power brake booster. hoping this solves the problem. thanks, carl
     
  4. CBODY67

    CBODY67 Old Man with a Hat

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    There are some electric vacuum "assist" pumps on the market, just for the purpose you mention. Augments/replaces the earlier vac cannisters that have been around a few years. Seems like there might be some OEM applications for the pumps, which might mean "salvage yard" items?

    MORE engine power ALWAYS points up the need to STOP, whether at the end of the drag strip or on city streets.

    Enjoy!
    CBODY67
     
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  5. Davea Lux

    Davea Lux Old Man with a Hat FCBO Gold Member

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    10 lbs of vacuum is not really enough to properly power the booster, adding the canister by itself is going to give you more volume, but not more vacuum pressure. You should go ahead with the canister, but you will need also need a vacuum pump to get the vacuum up to the 15-20 lbs the booster was designed to operate at. The diesel pickups ran vacuum pumps that put out some good volume and from a wrecking yard they are not all that expensive.Trick will be finding room to mount it and the canister.

    Dave
     
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  6. rags

    rags Senior Member

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    the ultimate solution: newport 008.JPG
     
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  7. commando1

    commando1 Old Man With a Hat on the Porch FCBO Gold Member

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  8. Davea Lux

    Davea Lux Old Man with a Hat FCBO Gold Member

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    What did you use the hydraulic booster off of?

    Dave
     
  9. CARL J KUSTREBA

    CARL J KUSTREBA New Member

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    hey all, thanks for the info..i put a vacuum canister on this morning and a little better. stop and go traffic still a bit sketchy for my taste. the engine is built, not by me. it does have a cam(i have the receipt) and the idle is choppy. i think next will be a vacuum pump. this is driving me nuts, as ive never had a problem like this before. last mopar i had was a 73 charger with the same motor (383) with a big cam and never had issues. thanks again, carl
     
  10. rags

    rags Senior Member

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    mark V lincoln. along with the disc brake rear. p/s pump brackets from '76 new yorker.
     
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  11. CBODY67

    CBODY67 Old Man with a Hat

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    I presume that 10" Hg of vacuum is with the car in "P"? Or in "D"? At what hot, base idle speed? Just curious.

    I always liked the firm pedal on the GM hydroboost pickups I had at work. Never spongy like the vacuum boosters tended to be, sometimes. When the booster seals "went", our customers said things got a bit messy inside, but the rebuild kits always seemed to work.

    Thanks,
    CBODY67
     
  12. 65sporty

    65sporty Old Man with a Hat

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    The Hydroboost
     
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  13. commando1

    commando1 Old Man With a Hat on the Porch FCBO Gold Member

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    I had to Google that.
    Why didn't it work?
     
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  14. 65sporty

    65sporty Old Man with a Hat

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    I am not quite sure I am following you, Rags has it and says it's the ultimate solution. Carl needs it or a vacuum pump because of the low vacuum.
     
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  15. rags

    rags Senior Member

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    exaclty. thank you, sir.
     
  16. fury fan

    fury fan Senior Member

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    When I first saw that, I thought it was the Teves electro-boost from the 84-92 Mark VII. Those are a 'neat' item but not suited for retrofit as you must learn how to repair them yourself. Still have 2 in my shed from my Mark 7 days of 15 years ago.

    Another option for a low-vacuum engine would be to convert to manual disc brakes - circumvents the vacuum problem, and better brakign to boot.
     
  17. rags

    rags Senior Member

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    no. i wanted something that would work. and not exactly a bolt-in but close to it.
     
  18. CARL J KUSTREBA

    CARL J KUSTREBA New Member

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    hello all, update...ordered vacuum pump. the 10hg of vacuum is at idle in park at 750rpm. hopefully this solves the problem, want the car safe for the family to drive and enjoy. the pump should be here by tuesday, will update later. thanks again,carl
     
  19. 70bigblockdodge

    70bigblockdodge Old Man with a Hat FCBO Gold Member

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    Add more initial timing and bring idle speed up, timing should increase curb idle speed.