Adjustable Rear Control Arms Setup

[happy4444]

Hey Guys, I’m currently installing Rear upper and lower Adjustable control arms and was wondering if you guys had any base measurements of more or less adjustment. The car is used on the street. I was going to just measure the Stock arms for a starting point unless you guys have any suggestions? I know every car is different, but some may have more knowledge than myself.

Thank You

 

[DeltaBravo]

I think I can help. I am not an expert, but I have successfully installed and adjusted the arms for proper pinion angle.

First you will need one of these:

Then read this:
http://www.wolferacecraft.com/pinionangle.aspx

 

[Ttype6]

I think I can help. I am not an expert, but I have successfully installed and adjusted the arms for proper pinion angle.

First you will need one of these:
View attachment 298583

Then read this:
http://www.wolferacecraft.com/pinionangle.aspx

This is not the correct way to adjust pinion angle. When the pinion and crankshaft/trans output shaft are parallel,your pinion angle is zero. Now rotate the pinion down one degree from where it was when it was parallel to the crank shaft and you have a pinion angle of one degree down. Or you could lower the rear of the trans until the crank shaft angle changes by one degree and you will also have a pinion angle of one degree down. The relationship of the pinion to the driveshaft has nothing to do with it. In fact,it is much easier to get an accurate measurement of the pinion angle with the drive shaft removed because you can use the machined surfaces of the yoke to set your angle gauge against. The place to read the crank shaft/trans output shaft angle is on the balancer/crank pulley.

The reason that we want some kind of downward pinion angle (in relation to the crank shaft) is because the pinion will rotate upward under hard acceleration. Soft rubber upper and lower control arm bushings allow for a lot more rotation than solid rod ends would allow. The objective is that when the pinion rotates upward,under hard acceleration, it will end up parallel to the crank shaft. When we have rubber bushings that allow a lot of rotation,we need to start with more downward pinion angle. Conversely,we don't need as much downward pinion angle when we use hard rod ends that allow for little rotation.

The simple goal,when setting pinion angle,is to have the pinion and crank shaft parallel under hard acceleration.

 

[Chuck Leeper]

Since they are adjustable set them to stock length as a baseline. work from there, to set pinion angle.
If you want to get into a detailed set up, once they are in, you can do a "centerline" measurement, to be sure the rear axle is in "square".