Home Alignment Experiment

I have squeal when turning my '72 Satellite Sebring Plus. It tracks straight when I let go (briefly!) of the steering wheel. I found an alignment shop (no computer) down the street. I have measured toe in twice and camber once now at home. It will be interesting to see how close my data comes to the shop data. For the record:

First attempt measuring alignment at home
12/3/2018 1972 Satellite Sebring Plus

Passenger tire toe in with rope method against rear tires
1 1/2” minus 1 1/4” = 1/4”
Driver tire toe in
1 4/16” minus 1 3/16” = 1/16”

total toe in 1/4” + 1/16” = 5/16”

Second attempt measuring alignment at home
12/7/2018 1972 Satellite Sebring Plus

Passenger tire toe in with even rope method (76 3/4” equidistant spacing front/rear)
5 3/8” minus 5 1/8” = 2/8” = 1/4”
Driver tire toe
5 5/8” minus 5 3/8” = 2/8” = 1/4”

total toe in 1/4” + 1/4” = 1/2”

rope to center hub cap distance:
RF 3.5”
RR 4.5”
LF 3.5”
LR 4.5”

1972 Plymouth FSM Page 2-20:
front track 59.6 with 10” brakes
front track 60.2 with 11" brakes
front track with disk brakes (mine) not listed
rear track 62.0” with 8 3/4 rear end
rear track 61.6 with 7 1/4 rear end
FSM specs for rear track with 8 1/4 rear end (mine) not listed
toe-out on turns 20 degrees inner/17.8 degrees outer
steering axis inclination 7 1/2 degrees

Camber measurements at home using 24” carpenter square, bubble level, tape:
12/7/2018 1972 Satellite Sebring Plus

Passenger tire
1 18/32” minus 1 12/32” = 6/32 = 3/16” = .69 to .75 negative degrees camber

Driver tire
1 18/32” minus 1 17/32” = 1/32” = .12 to .125 negative degrees camber

Just for fun “rear tire toe”:
Passenger tire (RR) 4 9/32” minus 4 10/32” = 1/32” toe out
Driver tire (LR) 4 9/32” minus 4 7/32” = 1/16” toe in

Tire temperature after 15 minute drive (I would expect these temps to lower and even out once alignment is corrected):

LF 136 outside tread
LF 101 inside tread

RF 136 outside tread
RF 113 inside tread

LR 98 outside tread
LR 98 inside tread

RR 113 outside tread
RR 104 inside tread

Camber angle formula calculated on this web page:
https://www.vcalc.com/wiki/KurtHeckman/camber+angle

Although my tires are on 14" rims, I used 15.5" in the formula because that is the diameter on the outside of the rim point that I was using to check.

As an alternate method to the internet formula above, multiply the measurement difference between top and bottom of rim and multiply by four. For example, my passenger front tire rim from above measured 3/16". So 3/16" x 4 = 12/16" = .75 degrees (negative camber)

IIRC toe should be measured between the front of the front tires and the rear of the front tires.

Dibbons said:

Camber measurements at home using 24” carpenter square, bubble level, tape:
12/7/2018 1972 Satellite Sebring Plus

Passenger tire
1 18/32” minus 1 12/32” = 6/32 = 3/16” = .69 to .75 negative degrees camber

Driver tire
1 18/32” minus 1 17/32” = 1/32” = .12 to .125 negative degrees camber

Click to expand...

Today I pushed the vehicle outside, leveled out the torsion bars to spec (1 5/8" between FSM measuring points) and checked camber again, using a small strip of cardboard from the rim to the carpenter's square cut to size top and bottom (then measured strips twice, once metric and once inch).

This time I got a little less passenger camber and a little more driver camber than last time.

For the record, here is the average of my measurements today:
Passenger Camber 4mm (4/32" - 5/32") = 0.46 to 0.58 degrees neg
Driver Camber 2mm - 3mm (4/32") = 0.29 to 0.46 degrees neg

If the shop finds camber around 0.50 negative that would be in the ball park for "street" recommended settings.

I was wondering where the bolts to adjust camber/caster were located. Never saw it explained or diagrammed until I found this April 1976 Chrysler Master Tech PDF booklet "Alignment Simplified":

http://www.mymopar.com/downloads/mtsc/340.pdf

The accompanying Master Tech video "Alignment Simplified" mentions wheel alignment "man", which got me to thinking: Has anyone had a female human being perform their front wheel alignment for them? I'm still waiting for that day.

http://www.mymopar.com/index.php?pid=141

Interesting story...

In my HS vocational auto shop class (school years 1984/86 and 85/86) I had two female students. The first grading period I was the partner of "the pretty one". She was 16, already had 2 children, actually knew what she was doing with the tools and a lot of the jobs and theory, and made a decent living selling pot.

I was first in the class until we got a new student and he turned out to be better
I'd rate this girl 5th out of about 20.

The third grading period I was partners with "the other one" who actually wan't terrible looking either. She also wasn't terrible with the mechanical end. Knew the tools better than the jobs though and not as much of a self starter. She was top half of the class, though.

Both of them got taught twice to do Mopar alignments. Once by the instructor and a second time by me. brakes and front ends were my specialty and the junior instructor used to bet other teachers that I could do front ends without the machine, or not need a second adjustment.

I have no doubt that the pretty one could have made it in the field if it was more lucrative than dealing pot.

The other one could have been a good tool crib or parts person.

On my home alignment on my 63 with stock suspension I set the caster with all the positive it will give which is only about 1 to 2 degrees positive at most. Then I set my camber around 0 and the toe at 1/8 in. Seems to work great on my car for street & strip. And the same front tires have been on it since 2006. Ron