Help correcting pinion angle


Need help adjusting the pinion angle in my 67 nova! I checked both angles and they are as follows:
crankline is -3 degrees and the rear is -5 degrees so I pretty sure that is going ot solve my vibration problem I know it shoud be zero which means I think hat i'll need to shim the rear up 8 degrees to make zero! Is that right? going to buy shims at 6 & 2 degrees to make the 8, maybe it's better at 6 degrees that's the answer I'm looking for! If the angle moves up 8 will that be safe? looking for some reassurance that this will work! and that i'm looking at the right number It's a street car with a and a 4 speed no racing just some fun now and then! Thanks Rich


Staff member
angles should be equal and like this diagram, and under 3 degrees, if your crank center line points down towards the rear at 3 degrees you want to shim the rear to point up at about 3 degrees and hopefully get them almost pointing at each other ,and yes its common to have a couple degree difference and yes under power the rear tends to rotate upwards, but ideally you'll have it set up so it won,t rotate enough to cause problems

yeah! I know you want to skip over the sub links, they are posted , HERE to help you locate and fix your problem, the reason your reading the thread in the first places so skipping the sub links only reduces your chances of correcting YOUR PROBLEM or REDUCING the chances youll LEARN A FEW NEW THINGS ... rigin=prod

04.gif ... ngles.html

viewtopic.php?f=71&t=8765&p=36080&hilit=u+joints#p36080 ... ion-1.html


tools, and info that might help ... 95998.html


image_3443.jpg ... mber=34214 ... ion=Search ... index.html




posting.php?mode=edit&f=71&p=2860 ... Swaps.html ... index.html



Staff member
Marks76ray posted this

Things are still going strong but just a little slow. By installing a different engine and transmission the driveline alignment needed to be checked. If the driveline is off it will cause u-joint misalignment and vibration or premature wear. There are all kinds of opinions on the net about this subject, so I read and read until I formed my own opinion. In my opinion the only real check for a street vette is the pinion yoke angle versus the face or transmission pinion angle. When I measured mine the transmission was down 3 deg and the differential was down 4 deg. That not good, the alignment had to be done. I started with the transmission and moved it up 3 inches. This only changed the angle 1/2 deg, so back down with it, there's no way to move enough to make a difference. I then started moving the differential, and things came together. If you have been following this thread I made a mod to the front diff support. I added to the bracket and slotted the bolt holes. This came in handy to move the diff up and achieve the correct angle. So now the diff is pointing up 3 deg and the trans is pointing about 3 1/2 deg. This is as close as I could get it. Here's some pictures to show what I an talking about.




End result on transmission side



End result on differential side



The modified front diff mount



And a few more pictures




I have been working on my front lower control arms to. I have bought the semi coilover front shocks that some of you run. Looking at the setup I didn't like how the shock bolted to the lower a arm, so my brain went to work. I know some of you have been using this setup with no reported problems. It's just while i'm here might as well fix it like I want it. The problem is, the shock bolts to the top of the spring pocket and the entire weight of the front sits on 2 nuts.:lookinup: My solution is to weld a plate in place for the shock to sit on.

This is how the manufactur wants it to be installed


Top view


Bottom view


See how thin the pocket is


Here's the plate I installed




The shock has more area to bolt to and the plate is 1/4" thick



All welded up



And the bottom side


I will use the existing bolt holes for a alignment and drill the new plate. Then it to the powder coat oven.:D

I'm having so much fun :cheers: Mark