Did I really mess this up? Rough alignment issues (uneven tie rod length) after steering box and spindle replacement

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chrismalish

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Gentlemen (and ladies), I would appreciate any thoughts on my situation. Car is a 1969 Dart Swinger 340.

I Just replaced manual steering box with Peter's BAC Borgeson unit, and the spindles with Cass/Doctor Differential spindles for Stage 2 disc brakes so I could move up to 5x4.5 bolt pattern. These spindles/knuckles have longer steering arms than what was on there, requiring the tie rods to be extended (leaving tie rods unchanged = pronounced toe out). To put everything roughly back together with wheels, car required more extension on driver's side tie rod than passenger side in order to have both tires facing forward or slightly toed in -- by several turns, maybe ½” to ¾” longer. This had to be done with car jacked up, but still looks good now that it is on the ground. I have not driven it yet.

Currently:
-- steering wheel is straight
-- Appears to be same number of turns lock to lock: ~1-1/3 from center to either direction.
-- I believe the stops to either side are the steering stops on the steering arms hitting the control arms, rather than running out of travel inside the steering box.
-- but as I said, tie rods are noticeably uneven....

Not sure how I could have messed this up, but maybe I did. Presumably this needs to be fixed, but not sure this can be fixed by shortening the driver side and lengthening passenger side, as I think this would result in wheels being oriented in a slight left hand turn -- which means to bring it back to center, I would have to take the steering box off-center (or at least where it currently is). Do I understand this correctly?

I understand that if I wanted to redo the whole shebang to double check my work, I could

1. Separate steering box from pitman arm.
2. Turn steering wheel back and forth to verify box is at center of travel. Re-mate to pitman arm.
3. Even the length between the tie rods and reinstall
4. roughly re-center the steering wheel if noticeably off by popping off the coupler, turning as necessary, and reinstalling (Borgeson unit and BAC coupler do not have master splines; steering wheel to steering shaft do...).

Questions before I go down this road:

1. Can one can get enough separation to allow the box to turn freely just by popping the pitman arm at the box without also unbolting the box from the frame, or the pitman arm from the center link? If so, maybe this is the path of least resistance...

2. Is that even necessary though? Hard to believe I stabbed the box in off center. However, Borgeson box is a bit hard to verify TDC (or whatever center is called on a steering box) when not on car, as lock to lock is not a nice round number. Instructions direct:

“Center the new box by turning the steering box from either left or right stop to center by approximately 1 13/16 turns. When the box is on center, turning will become stiff. Since the stiff portion of the sector does not provide exact centering, it is helpful to look underneath the vehicle when the pitman arm is fitted. When centered, the center of the pitman shaft and the grease fitting for the joint to the center link will be in direct line or very close with one another front to rear.”

I got close to center with the box on the bench (with master spline on box ~ fore/aft), then rationalized that installing the box on the pitman arm would force the box to center of travel, as:
  • The steering was centered when I drove into the garage
  • Pitman arm has master splines, which allow box output shaft installation in only 4 orientations, 90 degrees apart.
  • Distance from center link to steering box means Pitman arm can only be stabbed in one position: splined hole pointed to front and as close to box mounting location as possible. This puts master splines in pitman arm roughly fore/aft.
My assumption (and maybe this is wrong) was that if the box output shaft had to be twisted significantly (e.g., up to a quarter turn) mate to the pitman arm, that would translate into something like a full turn at the steering column input shaft, which would have been hard to miscalculate….

Also, after installation, I verified that in fact “the center of the pitman shaft and the grease fitting for the joint to the center link [were] in direct line or very close with one another front to rear.” I suppose that the box could be installed off center of travel and and allow this orientation, but then I would think there would be a huge disparity between turns lock to lock (like one turn to left, three to the right?), and that one would run out of travel inside the box before the steering arm steering stop hit the control arm on the "short" side....

Although I do want to take the car in for professional alignment, I don’t want to take this to the alignment shop if things are seriously out of whack and they can’t fix it by adjusting tie rods/caster/camber at upper control arms. First of all, nobody around me wants to even work on these older cars anymore, and definitely don’t want to mess with if there is something complicated wrong. And I don’t want to have to have it towed to the fancy race shop 25 miles away which will be expensive (tow, plus “specialist race car technician and alignment equipment” BS) and time consuming (for me – and this project has taken 10x longer than expected already….).

Thanks in advance for your thoughts.

Chris
 
@72bluNblu is a good resource.

For the avatar car, I had to get the tie rod lengths close as the toe change when the front end lifts is dependent in tie rod length. I used the Direct Connection (Mopar Performance) Chassis Manual book to measure/set mine. It forced me to have to pull and recenter my steering wheel but I have an aftermarket wheel anyway.

If the car is a daily driver or weekend warrior, I don't think I would worry about it.
 
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