Homemade crossmember for T56/DSE subframe

Discussion in 'High Tech Retrofits' started by Goat, Jan 12, 2018.

  1. Goat

    Goat Veteran Member Lifetime Gold Member

    1,788
    22
    Jun 7, 2001
    moncure, NC
    There are a couple of threads out there talking about this mini project I've been working on. I decided to start a new one without all the extra stuff.

    There are 3 or 4 companies that I'm aware of that make "conversion" cross members for this application. I am most familiar with the two I purchased and tried to use, Bowler and American PowerTrain. I was not happy with either design. To their credit, they tried to design to the DSE sub frame mounting holes, which is not ideal. Looks like DSE tried to put the mounting holes in the stock position. By doing so, the holes are several inches forward of where the actual cross member mounts to the T56. This creates a 'cantilevered' effect where the weight of the tranny/engine is not centered inline with the mount creating a moment arm - not the ideal situation for supporting a mass.

    Again, Bowler (which by the way was extremely supportive of this and refunded my entire purchase) and AP had to work with what they had and had to satisfy the needs of most people who would not want to do any welding on the sub frame.

    So, will their designs work? Sure they will, but there exists unnecessary stresses that I would not trust under severe conditions - just my two pesos...

    So I designed my own. I used 1x3" rectangular steel tubing. This design not only centers the weight of the transmission directly under the mount and exactly inline with the cross member, but as a side benefit will also increase the lateral stiffness of the sub frame. As mentioned earlier, the downside is I had to weld 90 degree brackets to the DSE sub frame (messing up their beautiful artwork). Rather than explain the process, I have included some pictures that should detail what I did. I have drawings of the design along with a cad model if anyone is interested in copying it.
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  2. czizza

    czizza Veteran Member

    873
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    Jan 8, 2004
    N. Massapequa, NY, USA
  3. badazz81z28

    badazz81z28 Veteran Member

    14,603
    158
    May 4, 2001
    Las Vegas, NV
  4. dave@ztech

    dave@ztech Veteran Member Lifetime Gold Member

    1,055
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    Mar 27, 2016
    NY
    Never mind the drawing, you should make and sell the part!! looks really nice!!
     
  5. Goat

    Goat Veteran Member Lifetime Gold Member

    1,788
    22
    Jun 7, 2001
    moncure, NC
    Sounds like a lot of work! I'm having trouble getting one car back on the road...

    Thanks guys for all the comments. Not interested in starting a new career, but will be happy to share what I have learned.:)
     
  6. CaliCamaro75

    CaliCamaro75 Veteran Member

    372
    22
    Sep 6, 2015
    Winchester,CA
    I'm interested. Cuz this is the setup im looking to run. Looks great from the pics!! Awesone job goat! !
     
  7. Mwilson

    Mwilson Veteran Member

    turned out great!
     
  8. Goat

    Goat Veteran Member Lifetime Gold Member

    1,788
    22
    Jun 7, 2001
    moncure, NC
    Thanks mike. Keep an eye out for the green machine - may be pulling in your driveway before long...
     
  9. Mwilson

    Mwilson Veteran Member

    Im excited!
    one of my neighbors has a 78 trans am and another has a 66 mustang we might all ride down to fayetteville soon be awesome if you rode down too! I dont expect you to make passes or anything but you may want to go down VERY easy by yourself once? I personally dont even want to get on my car out of the hole but I'll hit it in 2nd & 3rd. Cant wait to see you out here, hope your rear tires are semi sticky?

    set of these should make it alot more fun and safer on the street

    https://www.nittotire.com/competition-tires/nt555r-dot-compliant-competition-drag-radial-tire/






    .....
     
  10. iraqivet

    iraqivet Veteran Member Lifetime Gold Member

    445
    13
    Nov 7, 2012
    Hobart, Indiana
    Looks great. Hope I get my T56 transplant to work correctly.
     

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