Hot Rod Forum banner

Alignment question

3K views 21 replies 7 participants last post by  Bonneville462 
#1 ·
Hey guy I need some help with my 72 nova alignment. The drivers side is .5P camber and +2 caster and I'm trying to get the passager side to match with no luck. I can get my .5p camber but I can't get the caster. With two 1/8 spacers it's at .5p camber and -1 caster. What do I need to do to get it to +2 caster. I'm using a longacre bubble gauge and all the suspension parts are new.
 
#2 ·
You need to remove the shims from the front bolt. Adding one more to the rear may do it. I haven't done enough of them to know how much to expect so forgive me. But putting shims in and taking them out is part of an alignment on just about any car. You can't just know what is going to happen usually. Finding your way by adding or removing shims is common.

But if you remove the shims or even just one from the front that is going to swing the top ball joint back increasing your caster. But it will also move it out a little increasing your camber too. This is why you may need to add one to the rear, which will also increase caster but reduce camber.

If they are all new parts and this is off so much it sounds like the frame may be damaged. They sag some times with the tops rolling in.

But I am thinking you can make it work with the shims.

Brian
 
  • Like
Reactions: John long
#3 ·
Nova upper arms are non-symmetrical. The front bolt (straight portion) is mainly camber, the rear bolt (curved portion) is mainly caster, although an adjustment at one has an impact on the other.


So you can't just jockey shims back and forth (to change caster) like you can do on symmetrical arms and not impact the camber.


Like Martin says, there is trial and error with these cars. If the car doesn't pull, I would be less concerned about what the gauges read for caster.


Make a sketch of each side on paper so you can visualize how the arm moves.
 
#4 ·
Any arm is going to do the same thing, if you shim in the rear to bring the upper ball joint back to increase caster, that ball joint is also going to come in too, lessoning the camber. It will be a little different on a non-symmetrical arm but it happens the same on all A arms.

Right?

Brian
 
#7 ·
Correct. The only thing with non-symmetrical arms is that you can't jockey the shims around like you can do on a symmetrical arm without putting it back on the rack.


Symmetrical arms to change caster, move shims to the back or front and the camber stays the same. to change camber, add or remove equal front & back and the caster stays the same.
 
#5 ·
You know what's funny, we use to repair brand new Toyotas for Toyota of America, cars that had never even been to a dealer. I put the gauges on one one time and it was out of spec. :drunk:

Brian
 
This post has been deleted
#11 ·
This is what I found on the web plus a few more. I found one site that said for a street / strip car set it at +1 camber and -1 caster. I when with the factory setting for now until I can take it out for a drive. I live near Memphis and we're getting all the rain that's coming up out of Louisiana.

 
#12 ·
Yes high equal caster will cause the steering to return to center and stay on center best.
If you decide to go to the more negative values than spec on camber, you want to be in the slightly more positive toe value. Kinda slows inside edge wear and reduces wander.
 
#13 · (Edited)
I just crank the positive caster up with close to zero camber yielding slightly to the negative.. Take it for a ride and add more positive caster to the side it is pulling to by grinding a little off the cross shaft at the front bolt.. Usually the front bolts have no shims left if running max positive caster..

-Non symmetrical arms only- (GM A body and older rear steer cars)

A Shim change at the ball joint side of the control arm will change caster twice as much as camber..

A Shim change across from the ball joint will change caster the same amount as the rear but change camber very slightly, like a 10th or so..

A shim change at both bolts will only effect camber..

No need to check caster just max it positive with no pull and as close to zero camber as possible..

Get a 2x4 and with two nails put as close to the centers of the front tires as possible.. put it in the back of the front tires and center it, then move it to the front and check toe..

**** YOU ARE WASTING YOUR TIME UNLESS YOU HAVE THE FRONT TIRES ON GREASED SHEET METAL TO LET THE SUSPENSION RELAX****

On my 64 Bonneville I got 5-6 degrees positive by grinding some of the cross shaft at the front bolt down.. I learned this trick many years ago from an old time alignment shop owner who used the old bubble gauges..

Bottom line is if your car has the old style, rear steering linkage, forget it, it will never handle like a newer car and always be "on edge" due to the drag link being under compression... Chevy in 58 and then the GM A bodys in 64 were way ahead of the game when they came out with front steering linkage..
 
#14 ·
Old cars had less caster because the bias ply tires made their own caster as they rolled. When we made the switch to radial tires we needed more caster to make up for the difference in tires. My 73 Mavericks were originally spec'd at -1 caster and with radial tires they require a minimum of +2 degrees caster. We run 3.5 degrees with power steering on ours. We also run 0 degrees camber with a 1/16" toe in. The cars handle much better and tire wear is minimal.
 
#17 · (Edited)
Thanks...

I always think back decades ago to my old 62 Ford, manual steering, bias tires, after a turn it would snap back real hard and was a pretty nice car to drive..
We had Belgium block streets here and needed a soft ride.. The Good Year Custom Power Cushions were my favorite tire back then... The tire to get was the Pennsylvania Turnpike Cruiser tires...

It might look crude in the photo but driving slow back then was so much more enjoyable..



 
#15 ·
Great advise from everyone. I did use some homemade turn tables made from 2 pieces for sheet metal with grease in between them and they worked great. I'm still waiting for this rain to stop so I can drive it and see what happens. So if the car pulls to one side I need to add caster to that side correct. This alignment stuff is new to me but I'm listening and learning. On the passager side it wound up with no shims in the front and a coupe in the rear. So if I need more caster on that side it's going to be harder if I understand some of the post above.
 
#19 ·
must make sure that your parking spot is perfectly level.. had a friend try to do it on a slope parked sideways.. oops.. you will also want to measure between the upper control arm cross shaft mounting brackets from above.. there is an issue on some cars with crossmember sag..

easily fixed with some planning... and KNOWLEDGE Of what one is doing..

 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top