The Stovebolt Site Forums The Shop Area The HiPo Shop Setting pinion angle four link

Installing No Limit Engineering Fat Bar Four Link with Coil Overs. Situation: Body is off frame. Motor/Trans mocked in
sitting at 4 degrees negative (downwards). Frame is sitting
at 1 degree positive (down at front) That should put the engine/trans at 3 degrees negative. Front brackets are fastened
to frame rails with four bars in place. Housing brackets
are attached. Differential is sitting level on floor ready
to be tacked into place.
Question: If I place the pinion at 3 degrees negative (downwards) before welding, will I end up with 0 degrees or
parallel drivetrain?
That should also mean that the lower coil over brackets and
panhard bar bracket should be welded in at 3 degrees negative.
If you follow, please respond.
With no weight on the frame how will this end up?
Cheers

If you are using u-joint your pinion should be within 3 degrees of output.
I you are using a CV joint your pinion should poit at the output
upto abot 17 degrees max

I think you are on the right track.
Most people have a hard time understanding how a driveline should work. Therefore many people who think they know how to set it up are confused.

I have found that the best way for someone to understand how it works, and how to set the angles, is to read the instructions.
These two manuals will help with any and all driveshaft installation and geometry questions:

http://www.roadranger.com/Roadranger/servicesalesliterature/serachresult/RR_DSAG-0200

http://www.roadranger.com/Roadranger/servicesalesliterature/serachresult/RR_DSIG-3311

Personally I have printed them both and put them in a notebook, very handy.

Some important parts cut and pasted from the "Installation Techniques" manual (second of the two links above):

Rule #1, Universal joint operating angles at each end of a driveshaft should always be at least 1 degree.

Rule #2, Universal joint operating angles on each end of a driveshaft should always be equal within 1 degree of each other (1/2 degree for motor homes and shafts in front of transfer case or auxiliary device).

Rule #3, For virtual vibration free performance, universal joint operation angles should not bee larger than 3 degrees. If they are make sure they don't exceed the maximum recommended angles.


Please read the manuals, you will learn something, and be glad you did.

Grigg

In your case, because the truck is not finished and not at it's final weight, that can be a concern.
If the 4 link suspension is designed to keep the pinion angle the same over the range of suspension travel, then you are fine to go ahead and set it and weld.
If the travel of the suspension has an effect on the pinion angle (like a leaf spring suspension does) then you should have the truck closer to finished weight before welding permanently.

Grigg

Thanks;
I think I made a mistake on the description.
If I stay with 4 degrees on motor/trans, then the
pinion would have to face up the same amount to get
zero degrees.
The other factor is I am using an LS1 engine so sloping
downwards is not a factor, it could be level.
If thats where it ends up then I would face the pinion
downwards the recommended one to two degrees for the
four link. Without the load on the vehicle it makes
it interesting.
Cheers