Recommended cfm carburetor for a stock 305 V8 engine?

Discussion in 'Engine Topic' started by golfer, Feb 16, 2011.

  1. golfer

    golfer Member

    Messages:
    42
    Likes Received:
    0
    Joined:
    Jan 29, 2006
    What brand carburetor and what size in cfm will perform nicely for a 76 stock 305 V8 to be used mainly for a daily driver?

    Rebuilding the original Rochester is an option.
     
  2. BondoSpecial

    BondoSpecial Veteran Member Lifetime Gold Member

    Messages:
    8,694
    Likes Received:
    1
    Joined:
    Sep 20, 2004
    Location:
    Southern Maryland
    I would almost never suggest a Qjet but on a stock engine, I think that's going to be your best bet. You don't have to guess and check on jetting or bleed sizes or anything when the factory did that work for you. The qjet, rebuilt properly, should get the best MPG and have the best throttle response on that setup.
     
  3. marlin

    marlin Veteran Member

    Messages:
    242
    Likes Received:
    0
    Joined:
    Oct 27, 2009
    Location:
    Wantagh, NY
    Q jet for sure, Summit and Jeg's have rebuilts for sale as well.
     
  4. 78TypeLTCamaro

    78TypeLTCamaro Veteran Member Gold Member

    Messages:
    484
    Likes Received:
    12
    Joined:
    Mar 2, 2001
    Location:
    Waltham, MA. USA
    I just had my Rochester rebuilt for my 305. For an unmodified or slightly modified 305 that has the 2bbl manifold I don't think you can do any better with the stock 2bbl carb.

    If you replaced the manifold with one for a 4bbl, sorry I would not know the best.
     
  5. JONESYFXR

    JONESYFXR Veteran Member

    Messages:
    2,177
    Likes Received:
    0
    Joined:
    Oct 10, 2009
    Location:
    BUFFALO, NY
    My car came with a 305 when I bought it. It had an Eddy intake with a Holley 600cfm four barrel and it ran just fine.
     
  6. hhott71

    hhott71 R.I.P 11/19/18 Lifetime Gold Member

    Messages:
    14,377
    Likes Received:
    7
    Joined:
    Mar 30, 2001
    Location:
    Joplin Mo. 64801
    I'd recommend a 750 cfm carb,,,,, as long as it is a Q-Jet.

    You could find a 390 holley economaster, that's about all a 305 needs.
     
  7. sweetsoul

    sweetsoul Veteran Member

    Messages:
    598
    Likes Received:
    0
    Joined:
    Jan 12, 2010
    Location:
    Liberty sc
    rochester 2g 2 barrel.......just kidding , get a good dual plane intake and a 600 holley.you will be happy!
     
  8. 67 C-4 Camaro

    67 C-4 Camaro New Member

    Messages:
    7
    Likes Received:
    0
    Joined:
    Feb 14, 2011
    Location:
    Wash DC
    The rochester has problems when the secondaries kick in cause they are vac operated. I used to use a holly 600 with vac secondaries. This actually gave better fuel economy. Anything over 600 cfm is a waste of gas on that engine. Also don't be affraid to adjust your mechanical timing to 4 btdc. Smog era engines were retarded to help pass emission tests back then.
     
  9. SS2001

    SS2001 Veteran Member

    Messages:
    530
    Likes Received:
    0
    Joined:
    Jan 4, 2008
    Location:
    Lithia Springs, GA
    I would run more timing than that.
     
  10. my24ktrat

    my24ktrat Veteran Member

    Messages:
    1,226
    Likes Received:
    0
    Joined:
    Jul 5, 2007
    Location:
    Roch., NY
    ...As others have stated , either the quadrajet or a Holley 600, whatever is cheaper in your budget, just not the stock 2bbl , just my.02, DC:bowtie:
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.