manifold vacuum on chevy 350

Discussion in '40- & 55-Series Tech' started by john0089, Jun 22, 2005.

  1. john0089

    john0089

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    Where is a manifold vacuum hook up on a 350 chevy. I've posted some pictures...
     
  2. john0089

    john0089

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  3. ranger

    ranger

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    There is a vacuum port 2nd picture right under the airfliter. It is capped with a black cover, loooks like it is on the metering block. Also another source is where your vacuum advance for your distributor. You should also have a tap on the manifold inbetween the carb and the dist.
     
  4. 65swb45

    65swb45 Elder Statesman Supporting Vendor

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    Depending on what you need the vacuum source for, you might be able to T into the line for your brake booster as well.
     
  5. Wheelin4

    Wheelin4

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    On my Holley carb there is a full manifold vacuum port right next to the PVC vacuum connection. Not sure if all Holley's are the same though. I would go to the Holley web site as it has online manuals for most of their carbs.
     
  6. john0089

    john0089

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    Ok I am still trying to find more than one manifold vacuum source. Could I tap into the brake booster if I was using the vacuum for my th350 transmission? Are these manifold vacuum sources as well?
     
  7. lingo

    lingo

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    the second pic is of a mount for something should not be vacuum
     
  8. john0089

    john0089

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    Thats what I thought. So, the only manifold source is being used by the brake booster?
     
  9. lingo

    lingo

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    be sure to look on the manifold to see if there is a plug (threaded pipe type) that is in one of the intake runners. if not then the answer would be yes that is the only manifold vaccuum
     
  10. lingo

    lingo

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    oh yeah, i would also find a way to route that return spring away from the radiator hose. bad corrosion. maybe toward the rear off of the bottom of the bracket
     
  11. theo

    theo

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    Nope. Those are just threaded bosses for mounting stuff.

    Like ranger and lingo both suggested, Chevy intakes often have a plugged port behind the carb. It's a common place to get brake booster vacuum. If your Edelbrock has it you can replace the plug with a barbed fitting and be good to go. :)
     
  12. lingo

    lingo

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    you may be able to find a vacuum "tree" and replace the nipple this would give you more options and then you could plug what you don't need.
     
  13. john0089

    john0089

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    OK thanks for the help..im off to the parts store to find a vacuum "tree."
     
  14. john0089

    john0089

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    I got a t fitting and put it on the manifold vacuum with the brake booster. Do you think it will work?
    [​IMG]
     
    Last edited: Jun 24, 2005
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