1. Registration trouble? Please use the "Contact Us" link at the bottom right corner of the page and your issue will be resolved.
    Dismiss Notice

4.3 Merc Carb 450 Cfm on 225 V6

Discussion in 'Early CJ5 and CJ6 Tech' started by bnorth10, Jun 7, 2010.

  1. Jun 7, 2010
    bnorth10

    bnorth10 Wicked Willys Customs

    Joined:
    Feb 27, 2007
    Messages:
    128
    I know this has been discussed before but not in much detail about the marine 4.3 merc carb that is a quadrajet. It is 450 cfm and they sell reman ones on ebay for under 300. So it seems a pretty logical choice for the 225. The Holley 390 cfm is pretty pricey about another 100 higher and I am tired of kitting and adjusting this carter that is just evidently too big. Want to order it slap it on and make it purr...... just not quite ready for fuel injection coin.... although would be nice.

    Just initial thoughts but 4.3 vs 225 should be fairly close and the off road benefits of quadrajet would be nice.
     
  2. Jun 7, 2010
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor 2021 Sponsor 2020 Sponsor

    Medford Mass USA
    Joined:
    Aug 10, 2003
    Messages:
    23,615
    The Wagoneer crowd really likes the Quadrajet for their 360s. No personal experience, but the Quadrajet has a great reputation as an off-road carburetor. Seems to me you can't go wrong, if you're up to the task of tuning it.
     
  3. Jun 7, 2010
    colojeepguy

    colojeepguy Colorado Springs

    At the foot of...
    Joined:
    Apr 4, 2010
    Messages:
    5,971
    The Mercruiser 470 motor is actually 225 cubic inches, and some of them had Q-jets. I've been thinking about this if I can't get my TA470 running properly. The only downside to a marine carb is no ported vacum for the vacuum advance.
     
  4. Jun 7, 2010
    bnorth10

    bnorth10 Wicked Willys Customs

    Joined:
    Feb 27, 2007
    Messages:
    128
    Agree with comments. I just dont see too many terrible downside's to this option other than the cfm range is borderline
     
  5. Jun 8, 2010
    scott milliner

    scott milliner Master Fabricator

    Seattle Wa.
    Joined:
    Dec 17, 2002
    Messages:
    2,278
    That carb won't work for you. Send it to me.R)

    That carb should work for the 225. I have the 2bbl carb that came off a 4.3 ltr. The jetting is perfect for my 229 cid Chevy motor. The only draw back is marine carbs don't have throttle return springs, so you may find it hard to apply one.

    I have a the intake manifold for that 450 cfm carb. Still looking for the stock 2bbl intake, so I don't have to run the adapter.:rofl:
     
  6. Jun 8, 2010
    mb82

    mb82 I feel great!

    Charlottesville Va
    Joined:
    Mar 17, 2003
    Messages:
    2,706
    This has me wondering what I have. I have the marine carb and intake on my 229.
     
  7. Jun 8, 2010
    Warloch

    Warloch Did you say Flattie??? Staff Member

    Falcon, CO
    Joined:
    Mar 4, 2003
    Messages:
    5,238
    Qjets are nice if you find the smaller ones. Find a flaps that will let you dig through thier rods to find ones a bit larger to use with jets.... Test and run.

    FWIW - the TA470 works well - just use a vacuum gauge to tune with.
     
  8. Jun 8, 2010
    Dan66cj5

    Dan66cj5 Member

    Oregon
    Joined:
    Feb 20, 2003
    Messages:
    235
    I'm not familiar with the 4.3 merc carbs.. but there were cars that had the buick 231 v6's with Rochester quadrajets on them around the mid 70's and then the turbo buicks with the v6's had qjets as well. Edelbrock makes new qjets and sell jets/rods in alot of sizes.
     
  9. Jun 9, 2010
    bnorth10

    bnorth10 Wicked Willys Customs

    Joined:
    Feb 27, 2007
    Messages:
    128
    I think I may give it a go. The price isnt terrible and if it doesnt work out, a friend has a 390 holley brand new in the box sitting in his garage. May ask why I dont do that first but honestly I am a fan of a good running qjet over about any other carb
     
  10. Jun 9, 2010
    electricontr

    electricontr Member

    Denver Colorado
    Joined:
    Jan 12, 2004
    Messages:
    244
    You can use a Holley manifold and the Q-jet bolts right on w/o an adapter.
     
  11. Jun 9, 2010
    dave74

    dave74 Sponsor

    San Angelo, Tx
    Joined:
    Oct 27, 2006
    Messages:
    166
    The 85 Chevy C-10 with 4.3 used a QJet. I've got one setting in my shop waiting to go into a project.
     
  12. Jun 13, 2010
    bnorth10

    bnorth10 Wicked Willys Customs

    Joined:
    Feb 27, 2007
    Messages:
    128
    Ordered the carb. I will give an update when it gets here and I get it slapped on
     
New Posts