Part 1 rear end alignment. Part 2 in our series of tutorial videos that explain drag racing 4 link rear suspension set up shows you how to set pinion angle.
Pinion Angle 2 Piece Driveshaft Page 2 Street Source
4 link pinion angle. Make sure to adjust both the left and right equally and doube check after you are finished to make sure the rear end is still square in the chassis. 4 links i usually try to run 15 to 25 or less as needed for actual launch all cars launch some need more pinion angle to allow for wrap what i was taught many years ago was to fight to adjust so that at launch the wrap creates zero pinion angle and then as car unloads your runnin g angle comes back. With a 4 link car i dont think you need much pinion angle 1 2 degrees. Pinion angle simply refers to the angle of the differentials pinion shaft and yoke in relation to the driveshaft. According to bickel a ladder bar suspension normally requires degree of pinion angle a four link requires 1 2 degrees and a leaf spring suspension requires up to 6 to 7 degrees. If you are running a 4 link suspension system you can adjust the upper rear end links in or out to bring the variation back into where it needs to be.
My driveshaft also goes up from trans to rearend depends how low the car is in the back as well as the rearend type. This can lead to binding of the u joints and will hurt traction and break driveline components. Basically you want 3 5 down on the engine and trans 3 5 up on the rear. Leaf spring pinion angle shims. Be sure to check out all of the other videos in the series. Part 4 anti roll bar.
If the vehicle is equipped with leaf springs then you can use wedge shaped aluminum shims to move the pinion up or down. You never want the rearend setup with positive pinion angle. Just think of it like one cancels out the other and youll remember it then. Part 5 ride height. You want the pinion angle set equal to but opposite of the enginetrans. If youre running a leaf spring car the pinion angle is set by the welded perches on the axle housing.
This is when the yoke of the rearend is tilted upward more than the driveshaft. On a triangulated four link factory gm or ford the upper bars are also used to set the pinion angle by adjusting both uppers the same direction and same amount. Trans 2 degrees down rearend 0 degrees would be 2 positive. Part 3 pre load. Dana 60 12 bolt drive higher in the case than a 9 inch. A ladder bar or 4 link setup is much more rigid and therefore usually only needs 1 3 degrees.
A properly designed 4 link will have minimal pinion angle change over the stroke of the suspension. Operating similar to a four link suspension the force transfer link bar transmits forward thrust from the rear axle to. Part 2 pinion angle.
Gallery of 4 Link Pinion Angle
