Stock Magnum 5.2/5.9 camshaft w/carb?

Magnum Engine Swaps

  1. cudak888

    cudak888 1-Baker-11

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    Thanks! Just got home from taking the parents around for a spin in it. Spent all of Sunday slamming in an open 3.23:1 to replace the 2.76:1 gear, and it put puts around the neighborhood a lot better now.

    One thing did become apparent though: The car sags BAD with two passengers on one side. Pretty sure the rear leaf springs are due for replacements.

    Also wanted to put my Koni shocks on when I did the rear diff, but they only fit on top; the lower eyelet was just a tad smaller than the leaf spring plate. Gotta email Koni on that one; see what's up. Ironically enough, when I was checking the torsion bars because of the weight sag, it turned out the front shocks are loose. Looks like my front Konis will get pressed into duty quicker than I thought.

    P.S.: Anyone else here keeping sideburns alive? :p

    -Kurt
     
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    • 74SwingerSpe

      74SwingerSpe Well-Known Member

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      Hi cudak888,
      I just wanted to add a bit of information to all the great information already provided above. I've read in several places on the net that engines with carbs run better with cams that have a tighter lsa. I won't pretend to completely understand why, but I believe it has to do with cylinder pressure. As stated, a cam with a lsa of 114* like the stock magnum cam will work with a carb. However, if you want to optimize power a lsa of 110*, or even 108* with the same lift and duration is better. I can't find a detailed document I once read on this, but here is a Hughes Engines article that touches on it some.

      #7---Junkyard Jewel / Make Mine a 5.9

      If you want to skip the rest of the article, skip down to section "3. Camshaft". I wish I could find the other document, but maybe this might be helpful.

      Travis
       
    • alpha13

      alpha13 Well-Known Member

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      I havent been on here in so long! To answer the original question with my personal experience. I put a 5.2 in my 73 dodge D100 with an Edelbrock RPM and 600 Edelbrock carb on top. With no tuning I am getting 15ish mpg on the interstate at 65. The same MPG i got when the engine was in the Dakota i pulled it from. So no cam change is necessary for it to run. However is it optimal from a scientific standpoint comparing fuel injection to carb? I have no clue. I i didnt read the whole thread. So yes it will work but may not be optimal?
       
    • alpha13

      alpha13 Well-Known Member

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      Yes! I also love the Thrush Turbo, flows well and quiet at idle and cruise with full exhaust but sounds great when the throttle is down. No droning from what i can tell. Others might have a different experience. Plus they are relatively cheap! Summit branded turbo mufflers are the same as thrush i believe. Ive used both and dont hear a difference.
       
    • rumblefish360

      rumblefish360 So close, yet so far away FABO Gold Member

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      Same manufacturer I think but actual construction materials and how it is constructed will differ.
      The difference is computer controlled fuel delivery and ignition timing handled by the computer with an OD trans to assist in mileage.
       
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