thermoquad manifold, do i need these ?

Small Block Mopar Engine

  1. purplescamper

    purplescamper Well-Known Member

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    I have a stock spread bore thermoquad intake manifold on my 360, looking inside my manifold I notice I have whats called egr floor jets inside my manifold. since I'm not running egr stuff in my engine do I need these ?
     
  2. brasil

    brasil Well-Known Member

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    you donĀ“t need these floor jets,,, some people do block them ...with NPT plugs ... ( IF I would prefer to weld them ) because IF a plug is going loose.... the eingine is gone

    Greetings Juergen
     
  3. AJ/FormS

    AJ/FormS 68 B'cuda fb, Form S clone ... 367/A833/3.55s

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    Some guys block the passages at the head with thin stainless steel instead.
    Some guys weld or braze the bungs closed.
    Whatever you choose make sure the things don't leave home, cuz it will get real expensive, real quick.
     
  4. RustyRatRod

    RustyRatRod I was born on a Monday. Not last Monday. FABO Gold Member

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    Unless you can make the intake floor perfectly FLAT, there is zero need to change it. That intake flows almost as much as the 71 and 72 intakes. There is really no need to change it. You could end up doing more harm than good.
     
    Last edited: Jun 29, 2016
  5. alpha13

    alpha13 Well-Known Member

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    No those are not needed per say. I've heard of people milling them out for more plenum volume. I've never used one on any engine of mine so I wouldn't know how they would perform before you milled it vs after.
     
  6. perfacar

    perfacar Well-Known Member

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    hi, drill and tap for allen pipe plug. use Loctite. they will stay in. I did my 340 intake this way. as for flow, the71 n 72 without egr, was .05 faster over the 73 intake with egr mounds .just food for thought.
     
  7. alpha13

    alpha13 Well-Known Member

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    Maybe I'm wrong... I must be thinking of something else. Sorry!
     
  8. perfacar

    perfacar Well-Known Member

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    blocking intake exhaust will not affect egr. system, is has it's own passage. it comes out next to carb base. which is a huge vac leak!!!! block it down in the floor of manifold. then have no problem with vac leaks .
     
  9. Trevor B

    Trevor B FABO Gold Member FABO Gold Member

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    Are you referring to these holes inside? I'm curious about them too. Where do they go?
    RustyRatRod - are you saying they can just be left alone?
    a.jpg
     
  10. perfacar

    perfacar Well-Known Member

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    they need to be plugged. they go out to the egr valve, which sits next to carb flange. will cause a huge vacuum leak.
     
  11. RustyRatRod

    RustyRatRod I was born on a Monday. Not last Monday. FABO Gold Member

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    Leave them alone. The only thing you need plugged is the outside flange where the EGR bolts on. Trying to plug two holes in the bottom of the intake that you can hardly get to is stupid. Plug it where it's easily accessible. On the outside of the intake at the EGR flange. Just make a plate the same shape as the flange, drill the bolt holes in it, use a gasket or high temp RTV and bolt the plate on. Done.

    I don't know why in the hell so many people turn things into such a complicated task when the easy approach always works. It's your intake. Do it like you want.
     
    Last edited: Jun 30, 2016
    • Thanks! Thanks! x 1
    • perfacar

      perfacar Well-Known Member

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      the reason, I plugged them was to keep raw fuel from accumulating down in the egr passage!! open holes will let fuel get down in there. I figured , that's not very bright to allow that!
       
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