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smooth 56
06-26-2014, 07:21 AM
Done a search and did not find this topic on this site. I know this has been beat to death but I think that it would good for the site. I put a new tubular A arms this winter in the 56 and found that there are very few that still do alignments on the older car's. So let's discuss, I used a level and made a tool to set the tow. The only problem I had was setting the caster just didn't understand what to do.so what does every one else have to say on this topic?

Rick_L
06-26-2014, 09:28 AM
Sounds like you have the fundamentals. Camber can be measured with a digital level that's aligned with any thing that's parallel or square to the vertical centerline of the tire.

A crude but effective way of measuring caster is to measure the camber with the wheels turned 15 or 20º either direction. There is a bunch of math to get a real caster number from the measurement you take, but you can see what the difference in caster is from side to side. And if you want the car to go straight down the road without pulling, the caster needs to be equal from side to side, or maybe have a 1/4º more on the passenger side to account for the crown in the road.

Camber is changed by adding or removing shims at both upper control arm mounting bolts. Once you have the camber set, you can adjust caster. You get more positive caster without changing camber by removing a shim from the front bolt and adding it to the rear bolt. Once you run out of shims at the front, you can't get any more positive caster without changing camber too.

Sounds like you have the toe in measured.

The difference between the crudest of home equipment and a professional alignment rack is accuracy and repeatability. So anything you can do to make the floor level, surfaces true and precise, adding something under the tires to act as a turntable, etc., will improve your results.

For the specs, on a modified car with power steering use 0º camber to slightly negative, 3-5º caster, and 1/16" toe in.

chevynut
06-26-2014, 10:16 AM
Found this online:

"Once you've established the camber, caster is the next angle to check. With the bubble gauge installed on the hub, turn the tire inboard 20 degrees and level the gauge. Using the center caster adjustment knob underneath the gauge, zero the caster reading. Now turn the tire 20 degrees out and the gauge will read the amount of positive or negative caster.

Read more: http://www.carcraft.com/techarticles/ccrp_0910_diy_alignment_guide/caster_toe_in.html#ixzz35laf5dKb

Rick_L
06-26-2014, 10:43 AM
That's fine but a home made fixture doesn't have a "center caster adjustment knob". That instruction is for a camber caster gauge that mounts on the hub. There is a caster scale and a camber scale on it. Two scales takes care of the math.

smooth 56
06-26-2014, 11:37 AM
Yep I have saw those set up's they can get fairly pricey. I was just trying to get some info here so if someone done a search it would give a link to this site to maybe generate some traffic. I did finally get thing's worked out on mine. Have ether of you had any dealing's with the tubular control arm's? This was the first set that I have installed it was not a pleasant experience.:eek:

chevynut
06-26-2014, 12:35 PM
"Make sure your on a level and even surface (home drive is no use as it has a fall for rain etc)

You already know how to measure the camber angle so this is how to measure the caster.

With the wheels on the turntables and pointing straight ahead, zero your turntables.

Turn steering wheel to the right 20 deg (if your turntables have locks, lock them at this position.. if not get someone to hold the wheel steady)

Use the camber gauge as you normally would at 90deg to level surface, adjust the gauge to read ZERO.

Now turn the steering wheel left till you reach 20deg in the opposite direction (total of 40deg) and lock turntable.

Without altering the camber gauge setting, hold it at 90deg to level and the reading will be your caster angle http://www.driftworks.com/forum/images/smilies/smile.png

repeat on the left side wheel"


Sounds like it's hard to do without turntables.

Rick_L
06-26-2014, 01:25 PM
Turntables contribute a lot to repeatability and accuracy. A protractor on the turntable would add to that.

When I did the front end on my Nova, I just drew a line on the floor adjacent to the outside of the tire. The I drew two more lines at 20º to that line. I simply lined up the tire visually to the lines. I could repeat a caster measurement to less than 1/4º with the visual alignment. Mind you, that wasn't the accuracy, just the repeatability. Plus the same method and materials were used to measure and set the other side, so that whatever the lack of accuracy, it was the same on the other side.

Smooth56, can you elaborate on your difficulty with the tubular control arms? Is it installation or alignment?

smooth 56
06-26-2014, 02:17 PM
Turntables contribute a lot to repeatability and accuracy. A protractor on the turntable would add to that.

When I did the front end on my Nova, I just drew a line on the floor adjacent to the outside of the tire. The I drew two more lines at 20º to that line. I simply lined up the tire visually to the lines. I could repeat a caster measurement to less than 1/4º with the visual alignment. Mind you, that wasn't the accuracy, just the repeatability. Plus the same method and materials were used to measure and set the other side, so that whatever the lack of accuracy, it was the same on the other side.

Smooth56, can you elaborate on your difficulty with the tubular control arms? Is it installation or alignment?

Well it was a little of both. When I installed them I wasn't expecting anything to change but the alignment but when I set the car on the ground they had dropped it so low I couldn't drive it. Ended up putting new springs and drop spendals to get it back to where the original rid hight was. Then cam the alignment well I was just lost on that.I'v been working on car's as long as I can remember just not that much on the frunt end. That's kind of why I started this thread so me and others could understand whats going on.

Rick_L
06-26-2014, 04:31 PM
I'm a bit confused. The upper control arm won't do anything to ride height but it would change caster. So I'm guessing you got lower control arms too. Did you also go to coilovers? A tubular lower arm would usually change ride height unless you went to a coilover also, and even then, it would probably need to have a coilover mount that move the lower mount deeper into the control arm. This could have been changed.

Whose tubular arms did you use? Coilovers? What did you change to in order to raise the car?

I'm not challenging you on this, just wondering what combo of parts got you where you were and where you ended.

smooth 56
06-26-2014, 06:35 PM
I'm a bit confused. The upper control arm won't do anything to ride height but it would change caster. So I'm guessing you got lower control arms too. Did you also go to coilovers? A tubular lower arm would usually change ride height unless you went to a coilover also, and even then, it would probably need to have a coilover mount that move the lower mount deeper into the control arm. This could have been changed.

Whose tubular arms did you use? Coilovers? What did you change to in order to raise the car?

I'm not challenging you on this, just wondering what combo of parts got you where you were and where you ended.

Oh I know your not challenging me come on Rick your better than that lol. Well the part's I used were from gear head and I think the name was joit or joint should have brought up red flags by the name lol.Yes I changed both upper and lower and no coilovers with stock springs,still had to cut 1 coil,heits 2" droped spendells.The only reason
I changed them was the pass side lower was bent and everything I heard was these would make it drive better. Well I ran across a good buy and you can take it from there.

Rick_L
06-26-2014, 07:12 PM
Well I can't comment and have no knowledge of what you bought. It's good that you got the ride height right after the changes you made. I would recommend to others to stick with the name brands, at least you should be able to get a refund or exchange if it doesn't work the way you expect.

smooth 56
06-27-2014, 04:04 AM
Rick you couldn't have said it better stay with name brand's. Expensive lesson on my part,but to lay them beside the CPP they look the same.