[e3sean]

so i just bought a set of adjustible upper control arms i know how to install them but how do i go about setting the correct pinion angle?

[e3sean]

i also bought a set of lakewood lower control arms.

[trueblue01]

I have the Lakewood lowers with UPR adjustable uppers with the the solid spherical axel bushings. I also have the Comp Engineering anti roll bar. I started with adjusting the uppers to stock length and then adjusted to -4 degrees pinion angle with the car weight on the wheels. Total angle depends on the total deflection of the suspension at launch so fine tuning may or may not be necessary. My sig pic is of the car launching with that set up.

[e3sean]

ya my car squats like a mofo what do you use to deturmine -4*

[1slo5.0]

Originally Posted by e3sean so i just bought a set of adjustible upper control arms i know how to install them but how do i go about setting the correct pinion angle?

Pinion angle is the angle of the pinion in relationship to the Crankshaft Centerline OR the Driveshaft. To set pinion angle and preload you will need an angle finder that has a 360 degree face and uses gravity to pull the needle. These usually come with a magnetic base and are about 4" in diameter. You will need to have the car in full race trim with either you in the car or a stack of weights in the driver seat that weighs the same as you as well as fuel, nitrous bottle(s), etc. The car must also be sitting on the ground or on blocks to load the front and rear suspension and the car needs to be sitting at the same angle as it would be if it was on the ground. In other words, if the car sits level in full race trim on the ground with you in it, then it needs to be level when it is on blocks. Once you get that done then you can remove the bolt from the body side of the passenger side upper control arm and let the control arm hang on the rear end housing. If the body or axle housing moves sideways during this process you will need to start over. Put the angle finder on the front of the harmonic balancer and note the angle. Now you can put the angle finder on the flat portion of the pinion yoke and note the angle. Subtract the two measurements to get your pinion angle. Example, if you have -1 degree angle on the crank and +2 on the pinion the difference would be -3 which would be your pinion angle. Now you can adjust the driver side upper control arm to set pinion angle. Shortening the control arm will increase pinion angle while lengthening the control arm will decrease the pinion angle.



*With rubber bushings: Set Pinion Angle -3 degrees to -4 degrees*
*With polyurethane bushings: Set Pinion Angle -2 1/2 degrees to -3 degrees*
*With solid bushings: Set Pinion Angle -1 degrees to -1 ½ degrees*



Now you can adjust the passenger side control arm so the mounting bolt will slide in and out with no tension on it. Now your pinion angle is adjusted and you have zero preload on the rear suspension. If you don’t have a rear anti roll device then you can add preload in one direction or the other to help correct any issues with the car steering left or right on the rear tires. Zero preload is a good starting point. If you have an anti roll device then just keep the preload at zero and adjust the anti roll device to make the car track straight.

[e3sean]

Originally Posted by Darrell Pinion angle is the angle of the pinion in relationship to the Crankshaft Centerline OR the Driveshaft. To set pinion angle and preload you will need an angle finder that has a 360 degree face and uses gravity to pull the needle. These usually come with a magnetic base and are about 4" in diameter. You will need to have the car in full race trim with either you in the car or a stack of weights in the driver seat that weighs the same as you as well as fuel, nitrous bottle(s), etc. The car must also be sitting on the ground or on blocks to load the front and rear suspension and the car needs to be sitting at the same angle as it would be if it was on the ground. In other words, if the car sits level in full race trim on the ground with you in it, then it needs to be level when it is on blocks. Once you get that done then you can remove the bolt from the body side of the passenger side upper control arm and let the control arm hang on the rear end housing. If the body or axle housing moves sideways during this process you will need to start over. Put the angle finder on the front of the harmonic balancer and note the angle. Now you can put the angle finder on the flat portion of the pinion yoke and note the angle. Subtract the two measurements to get your pinion angle. Example, if you have -1 degree angle on the crank and +2 on the pinion the difference would be -3 which would be your pinion angle. Now you can adjust the driver side upper control arm to set pinion angle. Shortening the control arm will increase pinion angle while lengthening the control arm will decrease the pinion angle. *With rubber bushings: Set Pinion Angle -3 degrees to -4 degrees* *With polyurethane bushings: Set Pinion Angle -2 1/2 degrees to -3 degrees* *With solid bushings: Set Pinion Angle -1 degrees to -1 ½ degrees* Now you can adjust the passenger side control arm so the mounting bolt will slide in and out with no tension on it. Now your pinion angle is adjusted and you have zero preload on the rear suspension. If you don’t have a rear anti roll device then you can add preload in one direction or the other to help correct any issues with the car steering left or right on the rear tires. Zero preload is a good starting point. If you have an anti roll device then just keep the preload at zero and adjust the anti roll device to make the car track straight.

antiroll device meaning like the rear sway bar?

[e3sean]

and thanks for taking the time to write that up for me

[1slo5.0]

Originally Posted by e3sean antiroll device meaning like the rear sway bar?

No, an anti roll device. Much different than a factory type sway bar.

[e3sean]

Originally Posted by Darrell No, an anti roll device. Much different than a factory type sway bar.

ok then nope no anti roll device.