1965 barracuda rear rear end?

Early A-Body Discussions

  1. 6t5barracuda

    6t5barracuda Active Member

    Messages:
    29
    Likes Received:
    2
    Joined:
    Mar 20, 2014
    Location:
    tustin
    Local Time:
    7:58 PM
    So my 1965 barracuda is all original except motor, 273 bored.30 with a cam and an edelbrock 650 carb. Transmission was built too. So on my first drive, went and got gas then drove around the corner to lay a mean one wheel peel. My buddy followed me in his valiant and said both wheels were smoking. Later that night went over there And sure enough, I had two skid marks going 11 feet(and was going in a straight line):burnout:. I thought this original 7/25 rear end was a peg leg. How did this work? Thanks, -Derek
     
  2. moper

    moper FABO Gold Member FABO Gold Member

    Messages:
    15,757
    Likes Received:
    1880
    Joined:
    Dec 27, 2004
    Location:
    eastern CT
    Local Time:
    1:58 AM
    An open rear diff can still drive both wheels but it has to be the "just right" situation. If the traction and power are balanced, it will spin both tires. My '72 Demon slanty used to do that too.
     
  3. nerd racing

    nerd racing Well-Known Member

    Messages:
    454
    Likes Received:
    68
    Joined:
    May 18, 2009
    Local Time:
    7:58 PM
    My fwd mazda 2 does this when I peel them (clutch dump). I guarantee it's not limited slip.
     
  4. chryslerfat

    chryslerfat Well-Known Member

    Messages:
    13,394
    Likes Received:
    7415
    Joined:
    Aug 23, 2008
    Location:
    Monroe,Michigan
    Local Time:
    8:58 PM
    Some 7 1/4 axles were sure-grip.
     
  5. C130 Chief

    C130 Chief Mechanical Genius

    Messages:
    3,063
    Likes Received:
    209
    Joined:
    Nov 23, 2005
    Location:
    Boise, ID
    Local Time:
    6:58 PM
    Yep, Sure-Grip was an option regardless of engine. So until late in the 65 model year ALL a-bodies had the 7 1/4" rear, so if a Sure-Grip was ordered it would have been a 7 1/4". I don't know if they still did that after 66 or just installed an 8 3/4" if the Sure-Grip was optioned. At any rate, the Sure-Grip 7 1/4" is only marginally stronger than the open differential, and parts are rare as rocking horse sh*t.
     
  6. 64DartGTinAZ

    64DartGTinAZ FABO Gold Member FABO Gold Member

    Messages:
    2,583
    Likes Received:
    707
    Joined:
    Aug 14, 2010
    Location:
    Phoenix
    Local Time:
    5:58 PM
    Do another few burnouts...if the spiders get stripped, then you've got a peg-leg.

    ;-)
     
  7. Hipo65

    Hipo65 Yeah I'm "That Guy"

    Messages:
    645
    Likes Received:
    51
    Joined:
    Aug 9, 2013
    Location:
    Lincoln Nebraska
    Local Time:
    7:58 PM
    X2 on possable sure grip. my 65 dart gt had a 7 1/4 clutch style sure grip in it! It worked great so i sold it before i did any damage to it & made it just as worthless as an open 7 1/4.
     
  8. nerd racing

    nerd racing Well-Known Member

    Messages:
    454
    Likes Received:
    68
    Joined:
    May 18, 2009
    Local Time:
    7:58 PM
    I'm pretty sure my 7-1/4 was sure grip, it's worn out now though. When I first got it, it would do 11's. Now it's just a one wheel peel. I have an 8.8 to replace it over the winter.
     
  9. 65cudalover

    65cudalover Well-Known Member

    Messages:
    463
    Likes Received:
    12
    Joined:
    Apr 28, 2010
    Location:
    Wheeling, Illinois
    Local Time:
    8:58 PM
    Just keep in mind down the road you will definitely want to upgrade to a better rear end. My 65 formula S has been improved to a 8.25 rear and does very well with it. I had a 66 that I drag raced done with a 8.75 rear that was built to rock and roll as that car ran low 12's. Its all about money and how you want to go. Personally right now very happy with what I got and its perfect for a road car with 14 inch rally wheels and rides and runs very nice! Fit right in and no fighting to make it work.

    65 Cudalover
     
  10. MoparPhil

    MoparPhil Well-Known Member

    Messages:
    93
    Likes Received:
    6
    Joined:
    May 3, 2013
    Location:
    Provo, Utah
    Local Time:
    7:58 PM
    Jack up the rear end and spin one tire. If the other side spins the same direction it's a sure grip. If it turns the opposite direction it's an open rear end. I agree with 65cudalover, the 7.25 is not the strongest rear end for aggressive launching. If you do much more of that you will need to consider an upgrade. I have a narrowed 8.75 in my '65 Barracuda. BTW, when narrowing the rear end we calculated the dimensions to center the wheel in the wheel well. I can fit a 12" tire in there now with no tubbing.
     
  11. BillGrissom

    BillGrissom Well-Known Member

    Messages:
    7,360
    Likes Received:
    396
    Joined:
    May 10, 2009
    Location:
    Sacramento
    Local Time:
    5:58 PM
    Sounds like the famous scene in the movie My Cousin Vinny where the savy Jersey girl explains to the NC court how their cousin's car (Pontiac?) couldn't have left the spin-out marks the criminals did.
     
    • Like Like x 1
    • MoparPhil

      MoparPhil Well-Known Member

      Messages:
      93
      Likes Received:
      6
      Joined:
      May 3, 2013
      Location:
      Provo, Utah
      Local Time:
      7:58 PM
      Exactly!
       
    • Sreyno

      Sreyno FABO Gold Member FABO Gold Member

      Messages:
      72
      Likes Received:
      4
      Joined:
      Dec 20, 2012
      Location:
      Simi Valley, ca.
      Local Time:
      5:58 PM
      It still works fine behind a moderately built 360. Guzzles both tires at will. It did need axle bearings though.
       
    • m51

      m51 New Member

      Messages:
      3
      Likes Received:
      0
      Joined:
      Aug 22, 2013
      Location:
      Wisconsin
      Local Time:
      7:58 PM
      The 7 1/4 axles could be had with sure grip much later. I have a 4.5 bolt pattern 7 1/4 with sure grip. I busted 7 1/4's but others went for years without trouble behind HP small blocks 273 Commandos to 340s. I wouldn't worry about it so much that it is a "must do" if other things need help too.
       
    • 66durgederp

      66durgederp "pull hard, itll come easy"

      Messages:
      556
      Likes Received:
      56
      Joined:
      Aug 31, 2012
      Location:
      Zoo montana
      Local Time:
      6:58 PM
      had a 7.25 sure-grip in my 66. beat the holy hell out of that little beastie for a few years. never gave me any fits. recently swapped to an 8.25 for lug pattern and brake upgrade.
       
    • DartVadar

      DartVadar Well-Known Member

      Messages:
      1,298
      Likes Received:
      42
      Joined:
      Apr 3, 2013
      Location:
      Alberta
      Local Time:
      7:58 PM
      I have an open 7 1/4 behind my fairly stout 360, and on occasion it will spin both of the tires, but its usually a peg legger. Im pretty surprised its still going, i've given it some pretty good beatings!
       
    • chewy

      chewy Well-Known Member

      Messages:
      515
      Likes Received:
      14
      Joined:
      Dec 26, 2007
      Location:
      North Las Vegas NV
      Local Time:
      5:58 PM
      If u think about it, a sure grip 7 1/4 is stronger than a 7 1/4 peg leg, you are running aganst all the spiders instead of a pair.

      I took the rule of thumb with my 7 1/4 open, drive it and have fun with it, and if it breaks, upgrade it. When I broke it, it took about 9 months to find the setup for the price I wanted. 8 3/4 with 355s in it now.
       
    1. This site uses cookies to help personalize 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.