Check your Edelbrock Air Gap Manifold! If you have one - read this.

Discussion in 'High Performance Modifications' started by 71RS6SPD, Nov 26, 2017.

  1. CorkyE

    CorkyE Veteran Member Lifetime Gold Member

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    I'm doing an engine swap over this winter, kind of planning on using same intake. I've always used open gaskets, so I'll check with a 4 hole gasket and with a 4 hole 1/2" heat isolator I have.
     
  2. 71RS6SPD

    71RS6SPD Veteran Member

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  3. badazz81z28

    badazz81z28 Veteran Member

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    Isn't it all CNC? How can it NOT be perfect...I think it should be.
     
  4. CorkyE

    CorkyE Veteran Member Lifetime Gold Member

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    I know it looks to be sloppy manufacturing practices, but the butterflies aren't at the extreme edges, so there shouldn't be any interruption in air flow. This issue isn't solely owned by Edelbrock, I've seen post on other forums where guys are having to "modify" other brands. Still doesn't make it right though.
     
  5. 71RS6SPD

    71RS6SPD Veteran Member

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    I sent the above picts to Edelbrock and they stated that this is acceptable and there will be no performance effects. I cannot believe it - the fact that it will have 0 effect. I am not sure what to do.. send it back, use it as is (not for me), or open the plenum to match. What you guys think?
     
  6. 71RS6SPD

    71RS6SPD Veteran Member

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    badazz - these are not CNC. They are sand cast - hence the rough finish in the ports. There is probably a CNC involved in facing the water neck, dist mount, carb flange, manifold port faces, and probably drilling and threading but the manifold is manufactured in a sand mold - probably a soft one lol.
     
  7. 71RS6SPD

    71RS6SPD Veteran Member

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    The first one was off by almost 1/4.. this one is about 1/8 off in the same direction. I am leaning toward using it. Tentative plans are to machine the plenum a bit to remove any material protruding into the port that will disturb air flow.
     
  8. Camaro75LT

    Camaro75LT Masshole Staff Member Lifetime Gold Member

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    Boston-ish
    How do the new intakes compare to older ones? Has anyone checked a 20+ year old intake to see if being off is a new phenomenon? I can believe 1/8" is about normal unfortunately.
     
  9. 71RS6SPD

    71RS6SPD Veteran Member

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    I have checked an old one and the plenum is centered but it's a single plane manifold - much easier to cast.
     
  10. badazz81z28

    badazz81z28 Veteran Member

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    Yeah, I know they are casted in aluminum, but all the finish work is CNC. Is the problem where the holes are drilled or is it simply a casting flaw?
     

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