Alignment Problems

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chargerjoe68

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Hi I am kinda new to this sight but have noticed that there is alot of helpfull info on here and was hoping that someone in moparland can help me not sell my Dart. I recently finished the frontend on it all new moog suspension parts it is a 72 Dart 318 4 speed with 10 inch drums front and rear, everything is new! I took it to my shop I work at a Dodge dealer and Im a tech there, I put it on our alignment rack which is the newer updated version rack. I was able to get the toe, camber, and caster within specs but when I looked down the chart I noticed that the SAI (steering axis inclination) was in the red. Now I know that they use specs from the older bias ply tires but dont understand why this is. the specs for the sai was 7.3-7.8 and mine was 6.3. Also my included angle was out of spec.
From what I read it said I could have a bent front end part????
I was hoping someone could shed some light on this for me. Also my caster was within spec but was -0.5 and I thought you should shoot for negative. Any help would be much appreciated. :banghead:
Thanks in advance
 
Which side is the SAI out of spec on? out of spec SAI usually indicates a bent spindle. Is SAI the same on both sides? If the included angle and SAI are the same on both sides, let her rip. It's in the machine or how the heads were hooked up. No way in hell will both spindles be bent exactly the same amount. Also, you want positive caster for the street. .5 degree is pretty low. If that's about all you can get, you might get them to put in a little more toe in to make up for some high speed stability.
 
You should shoot for positive caster as the Skosh chart shows. If their stock bushings most likely you won't be able to even get it to 2 degrees positive caster. When they designed the steering on these cars bias ply tires were used and didn't require that much caster so the steering was designed to adjust in the range the tires worked. Only 2 remedies are possible. First being the offset upper control arm bushings OK mentioned. The other are aftermarket control arms that are designed for more positive caster. I haven't done enough front end alignments to know if it's possible the steering axis inclination issue may just be related to the negative caster setting and your alignment machine being much newer doesn't like those settings or it is possible you have a bent spindle or control arm. I thought that warning only shows up when you can't get the alignment set equal on both sides, but again my actual experience aligning front ends is limited. Since you work at a shop where you have access to an alignment machine try setting the caster for as much positive as you can get, (I could only get about 1 to 1.5 degrees positive out of mine with stock parts) and see if it still kicks up the steering axis inclination warning. If so, does it say if it's just one side, or does it specify?
 
Which side is the SAI out of spec on? out of spec SAI usually indicates a bent spindle. Is SAI the same on both sides? If the included angle and SAI are the same on both sides, let her rip. It's in the machine or how the heads were hooked up. No way in hell will both spindles be bent exactly the same amount. Also, you want positive caster for the street. .5 degree is pretty low. If that's about all you can get, you might get them to put in a little more toe in to make up for some high speed stability.

Ok thanks for your help my SAI was spec 7.3-7.8 mine is 6.2 on both sides in the red, My included angle is spec left 7.5-8.5 right 7.3-8.3 mine is left 6.8 red and right 6.2 same as sai on right diff on left.
here are the rest final reading of y car
camber left 0.6 right 0.1
caster left -0.5 right -0.7
toe left 0.14 right 0.12
total toe 0.26
i read that my included angle is the sum of my camber and sai????
also i have the moog 67-72 strut 2 piece improved bushings if that means anything???:happy1:
THANKS AGAIN:finga:
 
Forget about te SAI and included angle. It's fine. If it was one side out bad, that'd be a red flag. Don't worry about it. It wouldn't hurt to try to get some more positive caster though.
 
Forget about te SAI and included angle. It's fine. If it was one side out bad, that'd be a red flag. Don't worry about it. It wouldn't hurt to try to get some more positive caster though.

Ok thats fine do u think i made a mistake going with the newer strut rod bushings? Also when I try for more caster what should I shoot for on camber and toe?

Also if I get more caster will it change the sai?
thanks
 
Nothing will change the SAI unless you hit a curb or wreck the car. SAI is a built in angle. It is the downward tilt of the spindle when viewed from the front from the steering axis. you'd have to bend the spindle to change SAI. I like to see .5 camber, as much caster as you can get and about .25 degree total toe. Your strut rod bushings should be fine.
 
Not gonna say SAI Isnt IMPORTANT BUT . It's not really important unless you really get into extreme detail in angles . A bent part will be seen in caster /camber and toe readings.


Source: I'm an alignment tech at work
 
Not gonna say SAI Isnt IMPORTANT BUT . It's not really important unless you really get into extreme detail in angles . A bent part will be seen in caster /camber and toe readings.


Source: I'm an alignment tech at work
Ok so what is my best way to get this caster? Just work the upper ball back by moving the camber bolts or buy the offset bushings?
 
Nothing will change the SAI unless you hit a curb or wreck the car. SAI is a built in angle. It is the downward tilt of the spindle when viewed from the front from the steering axis. you'd have to bend the spindle to change SAI. I like to see .5 camber, as much caster as you can get and about .25 degree total toe. Your strut rod bushings should be fine.
So my camber and toe are good now? What is the best way to keep them numbers and get more caster? Thanks again
 
Nothing will change the SAI unless you hit a curb or wreck the car. SAI is a built in angle. It is the downward tilt of the spindle when viewed from the front from the steering axis. you'd have to bend the spindle to change SAI. I like to see .5 camber, as much caster as you can get and about .25 degree total toe. Your strut rod bushings should be fine.
Also does .25 degrees of total to mean toein or out
 
Ok so what is my best way to get this caster? Just work the upper ball back by moving the camber bolts or buy the offset bushings?

Buy the offset bushings, here's how to install them: set the arrows to point paralleled to straightest point on the body of the UCA, the correct direction of course, make this tool, lube em' up and stuff em in!:

http://www.forabodiesonly.com/mopar/showpost.php?p=1666568&postcount=22

Here is an article that goes into depth on how old Mopar suspensions are inadequate for today's road and driving habits.

http://www.allpar.com/history/mopar/front-end-alignment.html
 
You can get the offset bushings. Install them so that the hole in the bushings on the front of the arms are closer to the frame and on the rear of the arms so the holes are closer to the control arm. This will increase caster only while making no difference in camber. Of course, you'll have to have it realigned.
 
You can get the offset bushings. Install them so that the hole in the bushings on the front of the arms are closer to the frame and on the rear of the arms so the holes are closer to the control arm. This will increase caster only while making no difference in camber. Of course, you'll have to have it realigned.
I think I will just try to gett as much pos caster as possible with the new stock uppers that are in it currently. And just use the skosh chart on the camber and toe I can just plug it into the system and go from there.

What is 1/16 toe in equal to in degrees?
Also when looking at my rear toe, not that it makes a difference but i am getting 0.31 on left and -0.62 on right, I think I might have a bent wheel on the pass. side because when I balanced the wheel I noticed that it wobbled alot and it took almost 8 oz of weight to balance it.
So I beleive CORRECT ME IF I WRONG that the right rear wheel when compensating the heads is throwing the whole SAI off??? AGREE????

I have done nothing to the rear it is an 8 3/4 ss springs and rally wheels.
I have also read on here where some guys had to make a plate for the front hanger to offset it correctly???

Thanks again for the great help!!!!
:thumleft:
 
Geez, FORGET the SAI. Period, end of discussion. What part of that ain't you gettin? No, the rear end could be tied in a knot and it would not effect the SAI reading. I used to do cheapo alignments with no heads at all on the back. It makes no difference in the front. None, zero, zilch.
 
Here is a TSB on the 73 A-bodies showing the front end and the rearend has different widths. It states the front end was widened another 1.6" for a total of 3.6" wider than the rear. Would this be the case on the earlier cars also?

02-04-73D%20p1.jpg
 
Here is a TSB on the 73 A-bodies showing the front end and the rearend has different widths. It states the front end was widened another 1.6" for a total of 3.6" wider than the rear. Would this be the case on the earlier cars also?

[/quote]

x2 when I first bought my Swinger I followed behind and it indeed looked to be dog tracking.

PS: F*** SAI!!!!!!!!!!!!
 
here are the rest final reading of y car
camber left 0.6 right 0.1

Positive camber blows for radials. Your camber should be -.25 to -.5 for most street driving.

caster left -0.5 right -0.7

Again, your caster #'s are jacked. You want positive numbers here. With stock bushings, you're probably limited to something between +1 and +2. Set it for the highest positive camber you can get to match side to side.

toe left 0.14 right 0.12
total toe 0.26

Toe is actually pretty close to spec. But it'll change when you alter the camber and caster.

To maximize your caster, you'll want to adjust the camber bolts at the front of your UCA's so that they're all the way "out", ie, pushing the UCA's as far out from the frame as they'll go. Adjust the camber bolts at the back of the UCA's all the way "in", so they suck the UCA's as close to the frame rails as they'll go. Then check your alignment to see what the numbers are. That will be the most positive caster you'll be able to get, but you'll have to match things up side to side.
 
x2 when I first bought my Swinger I followed behind and it indeed looked to be dog tracking.

PS: F*** SAI!!!!!!!!!!!!

Another thing that can make them look like their dog tracking if the car has an 8-3/4 is the rear wheels aren't always perfectly centered. That's because of the design of the rear axle wheel bearings. The drivers side is fixed and you adjust the pass side in to get the proper end play putting it a little off center. My Cuda has all stock parts and the right rear tire is 1/2" away from the spring and the left tire is nearly an inch away from the spring making it appear that the axle housing is nearly 1/2" off center.
 
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