Upper trailing arm relocation trick

Discussion in 'Race car chassis tech' started by Gary Bohannon, Feb 28, 2018.

  1. Gary Bohannon

    Gary Bohannon Well-Known Member

    1966-67 Chevelle owners have relocated the upper trailing arms for improved IC.
    Drill new UPPER-FRONT holes at .75" lower than factory mount holes for much improved IC and traction. That seems like a simple way to improve instant center for traction. Have any of you tried this?
     
  2. buickdreamin

    buickdreamin I need a new old car ...

    I can see doing this with hiem joints or similar, but not the factory arms. Would be pretty tight.
     
  3. 455monte

    455monte Well-Known Member

    My 67 gs frame has both sets of holes.
    As far as i can tell its factory holes.
     
  4. Gary Bohannon

    Gary Bohannon Well-Known Member

    Mine has 2 factory holes, but using the lower hole does not provide lift or antisquat. Therefore, I guess they drill 3rd holes at .75" lower.
     
  5. 455monte

    455monte Well-Known Member

    I stripped a 64 special 1 time that had factory adjustable upper control arms.
    It had cam bolts so that the pinion angle could be fine funed.
    Any of you guys ever seen those on any other buicks from gm?
     
  6. Gary Bohannon

    Gary Bohannon Well-Known Member

    Mid sixties riverias had flat upper arms with several holes allowing length changes for pinion angle adjustment.
     
  7. hugger

    hugger Well-Known Member

    All 64 SS Chevelles had the adjustable uppers.
     
  8. Gary Bohannon

    Gary Bohannon Well-Known Member

    Put my 67 GS up on stands. No room to drop the f41 factory style braces 3/4 inch. The cost of tubular braces would be about as much as TA no-hop bars for raising the rear of the upper arms . Would like to try some TA's if I can find some used ones on here.








    gs
     
  9. BrianTrick

    BrianTrick Brian Trick

    I machined some solid bushings for the upper ears of the axle,then drilled the holes as much offset as a could,raising the mounting point of the upper arm to the axle.Every little bit helps when you are trying to keep it stock.
     

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