Buickstaged

iTrader: (1)

84 Bird - how to set/measure the driveshaft angle with adjustable torque arms? And, how to ensure the rear is square to the driveshaft and centered? Thanks, byron

sofakingdom

iTrader: (1)

Measure the angle that the transmission mainshaft or output shaft is at, then set the pinion to the same angle, minus about a degree or so. The object of the exercise is to get the pinion and trans shafts almost parallel with the pinion such that when the rear axle rotates slightly under power, it becomes exactly parallel.

The rear in these cars isn't "square to the drive shaft" to begin with so don't worry about that.

If you have an adjustable Panhard bar, set it so that the distance from the axle flange to the front LCA bolt location is the same on both sides. Resist the temptation to use the tires or the chassis as the reference, even though those things are much easier to see: since all that stuff is "soft" and imprecise to begin with, that would be about like jacking your house foundation to make the floor parallel to the picture hanging on the wall. Backwards.

If you have adjustable control arms, set them so that the wheelbase is about the same as stock, within a half-inch or so (the front wheels aren't always square so don't get too carried away with "precision" on this), and so that the rear "thrust angle" is centered on the fronts.

Doesn't matter if it's a 84, 91, etc.; Bird or Camaro. All the same car with different stickers and cupholders and minor sheet metal wrinkles.

QwkTrip

iTrader: (22)

In one sentence, square up the axle to the suspension pivot points on the car frame (where control arms attach), not the body.

Here is a video that will help you understand pinion angle and why it is important.

Buickstaged

iTrader: (1)

Sofakingdom and QwkTrip - Thank you for your response - only have a few minor details and then the car is set for shake down cruise. Thanks again - byron