Register now to get rid of these ads!

40's style rear spring set-up

Discussion in 'The Hokey Ass Message Board' started by model-a-fan, Mar 6, 2009.

  1. model-a-fan
    Joined: Oct 4, 2008
    Posts: 842

    model-a-fan
    Member
    from Kentucky

    Getting ready to weld my spring brackets to my rear end. I've done a search but most focus on the Model A rear spring. I'm using a 40's style rear spring and want to comfirm the placement of the brackets. How far apart should the be, eye to eye? (I'm using the spring behind Speedway brackets it if matters.)
     
  2. 32 thru 40 are 48in c to c of spring perch.
     
  3. model-a-fan
    Joined: Oct 4, 2008
    Posts: 842

    model-a-fan
    Member
    from Kentucky

    Mine measures 40 5/8 inches unmounted. So I have to spead it about 7.5 inches?
     
  4. model-a-fan
    Joined: Oct 4, 2008
    Posts: 842

    model-a-fan
    Member
    from Kentucky

    FYI, the spring is standard eye, about 11 inches tall, with 9 leafs (No 100% positive about the leaf count.
     

  5. Good time to make a spring spreader! You can get by without one but it is an easy project to make. There is a thread on here with pics from C9, myself and others. I will see if I can find it. T:)
     
  6. krylon32
    Joined: Jan 29, 2006
    Posts: 7,141

    krylon32
    Alliance Vendor
    from Nebraska

    We have always used the formula based on the total length of the main leaf center to center and mount the perchs the same distance apart c to c. We use a 44 inch main on our chassis so the perchs are 44 c to c. Remember this is total length c to c not the distance between the eyes when the spring is assembled. Does not apply to a T or A spring!
     
    Last edited: Mar 6, 2009
  7. Kato Kings
    Joined: Aug 22, 2006
    Posts: 691

    Kato Kings
    Member
    from Minnesota

    It depends on which year rear spring you have. Here is the breakdown.

    1935-1936 46-1/2" perch centers
    1937-1940 48" perch centers
    1941-1948 49" perch centers
     
  8. pasadenahotrod
    Joined: Feb 13, 2007
    Posts: 11,776

    pasadenahotrod
    Member
    from Texas

    Deduct 4-5" for the shackles which leaves you about 2.5" to spread the spring eyes.
    When you hook 'em up the spring shackles will be parallel to the ground. When you add the weight of the chassis they will drop down to 30-45 degrees and you have a correctly installed and tensioned Ford spring.
     
  9. model-a-fan
    Joined: Oct 4, 2008
    Posts: 842

    model-a-fan
    Member
    from Kentucky

    So I need to measure the main length as if it were flat? Then, how to I detemine the spacing on my perches? Sorry for not completely understanding. Just want to be sure prior to welding it all in.

    P.S> I do have a speader for the install.
     
  10. Kato Kings
    Joined: Aug 22, 2006
    Posts: 691

    Kato Kings
    Member
    from Minnesota

    These are the numbers that the stock rearends had for those years. If you have a stock spring wouldn't you want to use the numbers Henry used?



     
  11. model-a-fan
    Joined: Oct 4, 2008
    Posts: 842

    model-a-fan
    Member
    from Kentucky

    Sure, I'm not disputing that, I just want to clarify the identification process of the spring. I was told it was a 1940 spring, but need to confirm prior to welding the perches in.
     
  12. roundvalley
    Joined: Apr 10, 2005
    Posts: 1,776

    roundvalley
    Member

    I am going to go with PASADENAHOT ROD. Looking at it from a different direction. Center of spring eye to center of spring eye plus 4 OR 5" for the shackles equals the distance the RADIUS ROD PERCH EYES (CENTER OF EYE TO CENTER OF EYE) should be apart. Make sure you have the degree of tilt you want the pinion angle before you weld the mounts on the rear end.
     
  13. 31 A roadster on 32 rails.

    SoCal spring bracket - 44" apart on a 56" wide flange to flange measured at the axle flange.
    [​IMG]

    You'll need a custom length main leaf or the complete 40 Ford style spring from SoCal.


    Couple more views.
    [​IMG]

    [​IMG]

    Note flat crossmember, 1 1/2" x 2 1/2".

    The car sits quite low with this setup and height changes are easy.
    [​IMG]
     
  14. PASTDUEBILL
    Joined: Apr 6, 2008
    Posts: 830

    PASTDUEBILL
    Member

    I put the main leaf on, then draw the remaining leaves to it with a long threaded rod.
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 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.