Carburetor choice

Discussion in 'General Automotive Tech' started by dodgeguy, Mar 28, 2013.

  1. dodgeguy

    dodgeguy Well-Known Member

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    I am running a 350 Chevy engine that has been modified some. I don't know what was done to it, as it had been built when I bought the truck. The guy I got it from was not the builder, either, so all I know, it is a 350 with a solid cam that you can hear. I have always favored Quadrajet carbs on GM engines. However, mine has a new Edelbrock AFB on top of an Edelbrock intake. Having read many comparisons on these 2 carbs, and finding most favor the Quadrajet for most every reason, I am wondering if a carb change might be of some benefit. I am currently getting 16 solid MPG from the Eddie and something tells me to leave well enough alone. However, a couple more MPG and a little more HP would be worth the swap. Any suggestions?:confused:
     
  2. silverfox

    silverfox New Member

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    OK...I like QJ's. Everybody here pretty much knows that. However, if the engine now has an Eddie intake with a matching carb and is running good....I would leave it alone. My 2 cents.
     
  3. unkldave

    unkldave Cockroach Dave

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    Q=jets = great carbs and make a lot of power in front of an auto trans so no worries with that combo. Eddies work good too. What size is it? 1407/1411 = 750 cfm not sure about the 600? If mileage is what you're after , then for get you read any of this.
     
  4. DanR63

    DanR63 Well-Known Member

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    If the afb is running good leave it alone. I ran a afb (650 cfm) on a slightly modded 460 in my ranchero and it ran great for over 12 years! (about 75,000 miles of driving)
     
  5. WagonKiller

    WagonKiller Well-Known Member

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    i had an eddie on my 350 olds(stock intake) and it worked GREAT! also had it on a 350 chevy and it was just fine. I have one on my 455 poncho but am going back to the Q-jet as i think it worked better all the way around on this particular engine.

    Depending on just how "built" it is you may go backwards on the milage hard to say as we don't know what you have.
     
  6. dodgeguy

    dodgeguy Well-Known Member

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    Thanks for all the replies. I think the Eddie is a 600 CFM which should be about right for a 350 on the street. I know the truck will scream even with what is believed to be a stock 2:76 ?? rear gears. With gas prices, fuel mileage is always a concern, even though it is not my daily driver. I think 16 mpg is excellent for most any carbureted 350 stock or otherwise. I have pretty much decided to leave well enough alone. An overdrive tranny might be a better mod than a new carb.
     
  7. elagache

    elagache New Member

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    Don't count out Edelbrock AVS.

    Dear DodgeGuy and longroof fans,

    This suggestion is mostly for completeness, but it is worth saying. The Edelbrock AFB is simply Carter's original AFB carb now manufactured by Weber. Carter made a revision to the AFB called the AVS. Edelbrock markets that improvement as well under the same arrangement:

    http://www.edelbrock.com/automotive_new/mc/carbs_acc/thunder.shtml

    GM essentially never used the Carter AVS because it was introduced at about the time GM switched to the QuadraJet. However, other car companies did use the Carter AVS and got fuel economy that gave the QuadraJet a run for it money.

    There was a time when Edelbrock even marketed new Q-Jets, but alas they stopped making them. It would seem a savvy marketing decision, but for us consumers it may not be so good. Rebuilding a QuadraJet isn't easy and probably should be left to experts who are a dying breed. If you get a good one - wonderful! If you don't, how many times to you try to rebuild it or get another rebuilt model? There are a lot of fans of the Q-Jet, but there are also a lot of QuadraJet haters and in most cases that hatred was from personal experience.

    On the other hand, you can buy a new Edelbrock AVS and it is guaranteed to not have any rebuild voodoo included. My understanding is that the AVS is much harder to adjust correctly, but if you can, it will reward you with great all-around performance.

    So, something else to think about!! :idea:

    Cheers, Edouard :cheers:

    P.S. Oh, and I do I take my own advice . . . . . . . . Errr, . . . . . Not exactly!!

    But, I do very much hope that I've selected something that is even mor' betta'

    http://www.fuelairspark.com/fas/efi-systems/ez-efi-reg-self-tuning-fuel-injection/kits.html
     
  8. ross

    ross Well-Known Member

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    Since the Edelbrock(nee Carter) is a square bore carb you'll also need an adapter or a different intake to swap to a Q-jet.
    The Edelbrock is as modern as a carb can be, a very well regarded carb and proper tuned tuned you'll not likely see much more economy from a Q-jet even with it's smaller primaries.
    My $.02
     
  9. WagonKiller

    WagonKiller Well-Known Member

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    I have an edelbrock RPM on mine and i can mount an edelbrock or a q-jet will bolt right on
     

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