Magnum carb fuel system in early Abody.

Magnum Engine Swaps

  1. Gimike812

    Gimike812 Well-Known Member

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    I have a 64 valiant that was a /6 car. I am installing a 5.2L magnum with crosswind intake manifold and carter AFB carb, I will be using 70’s passenger car front accessories, stock magnum camshaft. I am trying to decide on what fuel system to use. I have a new in box mechanical fuel pump, I have read mixed reviews on the fuel pump eccentric. My other concerns are my car has 5/16” fuel sender and feed line. Am I better off installing a electric pump at the tank with a new 3/8s fuel sender and installing a regulator with a return line to the tank? Or is the camshaft eccentric with mechanical pump and the stock fuel setup sufficient for the 5.2L?
     
  2. Lelo Dart

    Lelo Dart * FABO Gold Member

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    Not trying to change the subject but you know that you have you use a LA timing cover and accessories to use a mechanical fuel pump right? If so, I think it wouldn't have a problem running with a 5/16" line and mechanical fuel pump. I have a 3/8" line and and the cheapo mechanical pump on a mildly hopped up 5.9 but it is still 5/16" coming out of the pump. No problems whatsoever.
     
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    • Bobzilla

      Bobzilla Well-Known Member

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      The stock 5/16" fuel line size will have no problem supporting the power level your stock 5.2 Magnum will make.
      I assume the eccentric issues you are referring to is the short snout adapter needed when installing the LA fuel pump eccentric on a Magnum short snout camshaft. These also work very well. Most people talk bad about it without ever actually using one. Just make sure everything fits well. Sometimes you need to file the key or extension a little, same as fitting any aftermarket part. Then, during final assembly make sure the camshaft and bolt threads are clean and dry, assemble with a little red Loctite, and be sure to properly torque the bolt.
       
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      • 67Dart273

        67Dart273 FABO Gold Member FABO Gold Member

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        I would use an electric pump PERIOD. I had a used Holley red for awhile, it worked well. Walbro makes a line of not-too-expensive pumps.
         
      • RustyRatRod

        RustyRatRod Lemmie see your b00bs. FABO Gold Member

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        5/16 fuel line is enough to support over 500 HP. So, there's no need at all to "upgrade".
         
      • Gimike812

        Gimike812 Well-Known Member

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        Thank you, Yes I do understand you have to use a LA timing cover, that would be the only way I can use the 70s car accessories on the front.
         
      • Gimike812

        Gimike812 Well-Known Member

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        Thanks to everyone else for the reply’s. I had a feeling I was over thinking the whole fuel system. Do you guys use a Fuel pressure regulator and a return line?
         
      • 67Dart273

        67Dart273 FABO Gold Member FABO Gold Member

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        I did. One thing about a rear pump and return line setup is that it helps discourage fuel boil/ and vapor lock.
         
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        • RustyRatRod

          RustyRatRod Lemmie see your b00bs. FABO Gold Member

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          I like to use them, yes. Especially with this ethanol crap gas we have to run. A good return system really helps.
           
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