Spohn 624 User 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:

First, had you measured your stock drive shaft angle and pinion angle before you removed

your stock torque arm, you would have calculated a 0 deg. TRUE pinion angle. This is how all

cars come from the factory.

Using an angle finder place it on the underside of the driveshaft and record the angle

indicated.

Next, place the angle finder under the pinion yoke and record the angle indicated.

Record both angles from the driver’s side of the car. On the driveshaft anything to the left of 0

is positive, on the rear end anything to the right of 0 is negative.

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 arms

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.

You don't want to drive around with your suspension preloaded all the time, it's a lot of

unnecessary binding on the u-joints and suspension. It should only be used when racing.

Here's a tip. When adjusting for your TRUE pinion angle, count the number of flats (or the 1/6

of a turn) as you turn the adjuster, to know how many it takes to adjust 1 degree of negative

TRUE pinion angle and in what direction (clockwise, or counter-clockwise). Once you know

that, then adjusting the arms at the track or before a race will take almost no time, and no

angle finder will be needed.

You will quickly learn that it does not take many turns to adjust the angle by several degrees,

so go slowly and check your angles often.