Follow these steps to square the rear axle in the chassis.

Front End    Rear End

Rear End

Squaring The Rear Axle ...
 

1. Make sure all components of the rear axle are installed on the axle, and are tight (put all components on the axle as shown here, use spacers in place of the wheels, and tighten the axle nuts).
2. With the rear arms off the car, put the rod ends (and jam nuts) on the arms.
3. Set the length of the rear arms as follows:
   •  Left Rear = 12 1/2" from the center of the splines to the center of the rod end.
   •  Right Rear = 11" from the center of the splines to the center of the rod end.
4. Install the rear radius rods in the chassis (but do not hook up to the rear end).
5. Install the rear torsion bars (ensure they are correctly greased).
6. Place the rear end in the car using 4” blocks.
7. Install the rear arms on the rear torsion bars.
8. Hook the rear arms to the birdcages.
9. Center the left rear arm so that it is centered in the middle of the flag of the left birdcage.

Leveling the Bird Cages ...
 

11. Hook up both (rear) radius rods up to the birdcages.
12. Using a level, adjust the left rear radius rod until the birdcage is 90 degrees to the chassis.  Note: There is a "flat" machined into the birdcage specifically for this purpose.
13. Using a level, adjust the right rear radius rod until the birdcage is 90 degrees to the chassis.  Note: There is a "flat" machined into the birdcage specifically for this purpose.

Attach the Ladder ...

18. Put the Jacobs Ladder in the car (being careful not to move the rear axle, birdcages, etc).
19. Adjust the rod end (in the right side birdcage) to the correct length so that the Jacobs Ladder attaches to the birdcage without moving the axle or birdcage.  This is simply a case of putting the Ladder into position, and aligning the holes in the Ladder with the eye on the birdcage rod end.  Keep adjusting the rod end in the birdcage until the two line up.
20. Put in the Jacobs Ladder bolt.

Recheck and Tighten ...
 

21. Recheck that the left rear arm is still centered in the birdcage flag, and both birdcages are 90 degrees to the chassis.
22. Tighten all jamb nuts (being careful not to move anything until all jamb nuts are tight), and Ladder bolt.

Front End

Put Front Axle in the Car ...

1. Put the front end in the car; using a 2" block on the left side, and a 2” block on the right side.

2. Make the two right front radius rods the same length. Make the (single) left front radius rod (approx) 1/8” shorter than the right side rods. Leave the jamb nuts loose.

3. Hook up all three radius rods, and the panhard bar (tightening all nuts/bolts enough so none of them are loose).

Offset Front Axle 1 1/2" To The Right ...

4. Pick a side, and measure from the king pin (center) to a straight edge that runs vertically from the top rail to the bottom rail.

5. With the other side, measure from the king pin (center) to a straight edge that runs vertically from the top rail to the bottom rail.

6. Increase/Decrease the length of the panhard bar until the measurement on the right side is 1 1/2” more than the measurement on the left side.

Squaring The Front Axle ...
 

7. On the right side; measure from the center of the rear axle to the center of the front axle.  The measurement should be 60 3/4".  Evenly adjust the right front radius rods until this measurement is achieved.
8. On the left  side; measure from the center of the rear axle to the center of the front axle.  The measurement should be 60 5/8" (for 1/8" lead ... adjust this measurement as desired).  Adjust the left  front radius rods until the correct measurement is achieved.

Set the Caster ...

9. Measure the (current) angle of the car front and back by putting a angle finder on the bottom rail.

10. Mark the top of the right front radius rods with a sharpie (and any other pencil, pen, etc).

11. Place the angle finder on the right front steering arm.

12. Adjust the radius rods until the angle finder reads between 8 and 10 degrees, compensating for the (current) angle of the car. The exact amount of caster will vary depending on driver preference. A good starting point is 10 degrees. Generally, the more caster in the car, the better the car will feel to the driver.
     

Recheck and Tighten ...

13. Recheck all the of the measurements above to ensure nothing moved during squaring. If any measurement is not accurate, undo all the steps, and restart the entire process at step 4.

14. Once all measurements are correct, tighten all jamb nuts (being careful not to move anything until all jamb nuts are tight).

Set the Toe ...

15. Determine the amount of toe required. This is a driver preference, usually between 1/8” and 1/4". A good starting point is 3/16”.

16. Loosen the jamb nuts on the tie rod.

17. Putting a tape measure through the frame, measure the distance between the left side and right side wheel beads at the inside bead at the back of the wheel (the portion of the wheel “most” towards the back of the car).

18. Putting a tape measure through the frame (close to the torsion tubes), measure the distance between the left side and right side wheel beads at the inside bead at the front of the wheel (the portion of the wheel “most” towards the front of the car).

19. Adjust these measurements by turning the tie rod in/out until the front measurement is 1/8” (or the desired amount of toe) larger than the back measurement.
    Repeat steps 15 to 18 until the desired amount of toe is reached.

20. Tighten the tie rod jam nuts.

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