Spohn H-605 - Manual (Page 2)

Setting Pinion Angle
There are two angles to deal with:
1) Driveshaft angle
2) Pinion angle
You subtract pinion angle from driveshaft angle to get TRUE pinion angle
Here's how you do it:
Using an angle finder place it on the underside of the driveshaft and record the angle
indicated.
Next, place the angle finder on the underside of the pinion yoke and record the angle
indicated.
Subtract the pinion angle from the driveshaft angle. The result is "TRUE Pinion
Angle". In order to apply preload you need negative TRUE pinion angle. Adjust the
upper control arm so that the front of the pinion goes down; continue to check each
angle until the pinion angle is more degrees down than the driveshaft angle.
We recommend -1 degrees on a mildly modified daily driven car. For high
horsepower applications we have gotten the best results with -2 to -3 degrees. There
is no reason to run more negative then that, it will actually hurt your performance
because it will induce driveline bind. The goal here is 0 degrees pinion angle when
under load.