Register now to get rid of these ads!

Technical How much hp/tq can torque tube setup handle

Discussion in 'Traditional Hot Rods' started by draggin49, May 21, 2020.

  1. draggin49
    Joined: Jun 9, 2014
    Posts: 93

    draggin49

    I was just trying to get some input from guys with experience running higher HP while retaining torque tube setup, what’s the most power they’ve run without breaking ?
    What’s the ballpark horsepower range where you really need to convert to open drive ?
     
    Last edited: May 26, 2020
  2. fourspd2quad
    Joined: Jul 6, 2006
    Posts: 682

    fourspd2quad
    ALLIANCE MEMBER

    When you start throwing hp at the rear end the torque tube part of the factory design in not the weak link , the axles and the keys are.
     
  3. Bear40
    Joined: Feb 17, 2007
    Posts: 19

    Bear40
    Member
    from Minnesota

    I think an Outlaw sprint car is about 900 hp, and they use a torque tube.
     
  4. draggin49
    Joined: Jun 9, 2014
    Posts: 93

    draggin49

    I’m at around 350 horsepower, is there a torque tube closed drive setup that could handle this or should I do an open drive conversion ?
     
    Register now to get rid of these ads!

  5. draggin49
    Joined: Jun 9, 2014
    Posts: 93

    draggin49

    Yeah , I am thinking I’m gonna go to s stronger rear than my existing early banjo .
     
  6. justabeater37
    Joined: Jan 1, 2009
    Posts: 1,267

    justabeater37
    Member

    They make an axle upgrade to slip in axles. What are your plans? Tire sizes? Dropping the clutch at high rpm? What car? Weight? Driveshaft length? So many questions. All play a part. Like said above, the closed torque tube can be pretty stout.
     
    MO54Frank and warbird1 like this.
  7. justabeater37
    Joined: Jan 1, 2009
    Posts: 1,267

    justabeater37
    Member

    31hotrodguy likes this.
  8. Rusty O'Toole
    Joined: Sep 17, 2006
    Posts: 9,147

    Rusty O'Toole
    Member

    What kind? 30s Chevs were notorious for breaking axles with the stock 80HP six. Forties Fords could handle up to 150HP without too much trouble especially if you avoided drag racing starts. Some big cars like Buick were even stronger.
    As others have pointed out there are custom made torque tube setups and quick changes that will handle anything you can throw at them, for a price.
     
  9. mkubacak
    Joined: Jun 20, 2005
    Posts: 154

    mkubacak
    Member

  10. I had a Buick powered 47 Chev, in which I ran a Buick transmission, and torque tube rear end. I abused the crap out of it, and never had a lick of a problem.
    Bob
     
  11. And the traditional way to do this was using Mercury axles. I will see if I can dig up the old article that I posted 15 or more years ago.
     
    pitman and seb fontana like this.
  12. 51504bat
    Joined: May 22, 2010
    Posts: 1,830

    51504bat
    ALLIANCE MEMBER

  13. jaracer
    Joined: Oct 4, 2008
    Posts: 324

    jaracer
    Member

    Sure do.
     
  14. jaracer
    Joined: Oct 4, 2008
    Posts: 324

    jaracer
    Member

    Back in the 60's a buddy had a 39 Ford with stock drive train and a hot flathead. Never had a problem. Then he sold the flattie and installed a nailhead out of a 54 Buick, probably a 264. The first thing to go was the 39 trans. There was a guy in town that would machine and install later gears in the 39 case which fixed that problem. That moved the weak spot to the rear axle. Broken keys, split hubs, broken axles and then he sold the car.
     
  15. draggin49
    Joined: Jun 9, 2014
    Posts: 93

    draggin49

    Trans is a tremec t170 converted to work with closed drive setup . Went that route to avoid having to change rear suspension .
     
  16. justabeater37
    Joined: Jan 1, 2009
    Posts: 1,267

    justabeater37
    Member

    What car are you talking about? We are all assuming Ford banjo, but there are others. What car are you building?
     
    31hotrodguy likes this.
  17. draggin49
    Joined: Jun 9, 2014
    Posts: 93

    draggin49

    1932 Ford , original banjo housing with aftermarket slide in axles .Stock torque tube setup that was shortened to fit .
     
  18. southcross2631
    Joined: Jan 20, 2013
    Posts: 3,753

    southcross2631
    Member

    Depends on the traction. spinning forgives, hooking up doesn't.
     
  19. draggin49
    Joined: Jun 9, 2014
    Posts: 93

    draggin49

    I’m running firestone bias ply 750x16 rears .
    Not that big of a contact pattern on them , don’t seem like tires that are ever gonna hook really well
     
  20. The banjo is not the first thing that will break in the drive line with a torque tube. It’s the trans. Yeah you might shear an axle key or break an axle. But I can almost guarantee, you will blow up the trans. Before you blow up the rear. Even the best built 39 top loader trans will not stand up to a heavy foot and lots of power. I’m very gentle on my 39 trans with a 283 in front of it for that reason. If you want a traditional set up with a torque tube, track down a 37 lasalle trans and convert it to torque tube. That one will hold up. Much stronger than the ford trans.
     
    lothiandon1940 and 31hotrodguy like this.
  21. irishsteve
    Joined: Jan 10, 2017
    Posts: 727

    irishsteve

    Keep in mind the 32 rear isnt much more than a model A rear.Later years have much more metal for internal support near the pinion.Henry had 65 HP in mind when he designed it.As he upped the HP he strengthened the center section.
     
  22. DeadFast 33
    Joined: Feb 3, 2003
    Posts: 439

    DeadFast 33
    Member
    from Santa Cruz

    Blown Arduns like to break stuff!


    @eights_aces_flip on instagram
    eightsandacestattoo on Facebook
     
  23. draggin49
    Joined: Jun 9, 2014
    Posts: 93

    draggin49

    44591F31-F911-47A8-8D75-0E4CDACC0412.jpeg
    no clutch dump and it pulled the rear of torque tube off the rear end . It was way beyond what the torque tube was ever meant for so I can’t be surprised or mad at the results .
    I have a feeling open drive and a stout rear end may be in my future.
     
  24. uncle buck
    Joined: Feb 13, 2007
    Posts: 1,590

    uncle buck
    Member

    That looks like an early style banjo rear with the round coupler , basically a model A design. The later 32 rear and newer have a scallop looking coupler and are stronger.


    Sent from my iPhone using H.A.M.B.
     
    kidcampbell71 likes this.
  25. HotRodWorks
    Joined: Dec 6, 2005
    Posts: 257

    HotRodWorks
    Alliance Vendor

    It appears that the torque tube bolts were not tightened before the first test drive. That joint will not pull apart like that if the bolts are torqued properly. The bolts are now extra loose and the weight of the car is on the spring behind the rear axle pushing the front of the banjo up. That is why the top is gapped more than the bottom.
     
    31hotrodguy and kidcampbell71 like this.
  26. Russco
    Joined: Nov 27, 2005
    Posts: 4,131

    Russco
    Member
    from Central IL

    I know how much mine couldn't handle... driveshaft.jpg
     
  27. HotRodWorks
    Joined: Dec 6, 2005
    Posts: 257

    HotRodWorks
    Alliance Vendor

    Is that an original or aftermarket?
     
  28. 31hotrodguy
    Joined: Oct 29, 2013
    Posts: 1,480

    31hotrodguy
    Member

    Ohio George Montgomery ran the torque tube rear in his gasser and had good success. I did a read up on it about a year ago when I was gathering parts for my 34 chassis with Cadillac 365. It’s worth looking up.

    Scott


    Sent from my iPhone using The H.A.M.B. mobile app
     
  29. Axle key's were my problem. HRP
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2020 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.