Alignment question

[kensmith]

I have a stock 78 Spider with radial tires. What is the best alignment specs to maintain straight forward steering on the highway? I want to take it to Goodyear for an alignment but I don't trust their specs all that much. Thanks!

[mdrburchette]

According to the Fiat factory manual for a 1973 Fiat Spider fully laden with 2 persons and 44.092 lbs of luggage weight:
Inclination angle 6°
Caster angle 3°30' + 30'
Camber 0°30' + 30'
Toe-in .12 + .039" (3 + 1 mm)

I don't have a Spider newer than a 1972 but I don't think there would be much difference in the alignment specs. I run a little more neg camber on mine.

[So Cal Mark]

in order to go straight on a road with a crown, some caster spread has to be set. Rule of thumb is 3/4 of a degree more positive on the right side than left for the average road. If you drive only freeways, you can get away with a little less spread. Generally, city streets may have about a 5 degree crown, freeways a bit less

[azygoustoyou]

If you find the spec's for the 78, please share it with us. I have one and will need them also. Thanks

[kensmith]

I have found 4 or 5 references to alignment but all indicate laden (400 lbs approx.). I can't find anything with unladen numbers as the alignment shops are not going to put weight in the car when aligning it. So how does one compensate for unladen? Also, I know there are different caster adjustments for different kinds of driving. I think I would like more caster as freeway driving seems a little unstable. Thanks!

[kensmith]

Ok, not many responses so will go with:

Camber 0*
Caster 3*
Toe-in .12 to .04 inches

[htchevyii]

We have weights that we put into the cars if required, know any weight lifters?

[kensmith]

I don't have any weights to put in the car. I was thinking maybe there is a way to compensate for the weight?

[azruss]

i have never seen a non-laden spec. I have used the following: bags of soil, hay bales, 5 gal cans of water, wife, kids, wife and kids, bags of sand, 33gal garbage cans full of water (careful on these so they wont tip. tie them to the seatback).

[kensmith]

Ok, so had Goodyear do the alignment with their Hunter laser system. Toe-in was way out of spec. The caster was good and so was the camber. Here id the final specs:

1978 Fiat 124 Spider unladen:

Camber: L-side .4*
R-side .3*

Caster: L-side 2.3*
R-side 3.0* (allows for road crown)

Toe; L-side .11*
R-side .09*

SAI: L-side 5.4*
R-side 5.5*


Included angle:

L-side 5.8*
R-side 5.9*



Cross Camber: 0*
Cross Caster: -.7*
Cross SAI: -.1*
Total Toe: .20*

[124ADDHE]

When I didnt realise that the car needed to be loaded I setup the toe-in to 2mm, when I subsequently read about the spec only being accurate while loaded, I checked the toe and was suprised that it was way out and I then had to do it correctly. OK tire in Salmon Arm (8 years ago) sold me tires and a 4 wheel alignment, my tires wore funny, I went back in and they then looked in their book more closely and realised that the car had to be winched down to bring the front crossmember to 6" from ground to correctly setup alignment!

[kensmith]

When I didnt realise that the car needed to be loaded I setup the toe-in to 2mm, when I subsequently read about the spec only being accurate while loaded, I checked the toe and was suprised that it was way out and I then had to do it correctly. OK tire in Salmon Arm (8 years ago) sold me tires and a 4 wheel alignment, my tires wore funny, I went back in and they then looked in their book more closely and realised that the car had to be winched down to bring the front crossmember to 6" from ground to correctly setup alignment!

The guy at the alignment shop said they have no way to add 400 lbs to the car. He used his computer figures to do the alignment and I hope this is updated information on the software to take the unladen weight into consideration. He also told me if it does not feel right to bring it back and he will make changes at no extra charge.

[geert]

for what"s worth :

for a fiat 127 (front wheel drive etc) I have figures loaden and unloaden, might help to get an idea ( but front wheel drive is not the same as rear wheel drive):

loaden : caster +2°30' to +3°30'
camber 0°30' to +1°30
toe in/out +2mm- -2mm

unloaden : +1°30 to +2°30'
+ 1°15' to +2°15
toe out 2.5mm to 6.5mm

(ref :vraagbaak fiat 127, P Olyslager ( a Dutch guy))

hope it might help.

you can try to do it yourself ( gave me an interesting sunday a couple of months ago ( see other topic ) , finally some use for the stuff learned a long time ago in school about tangens and sinus. And two of my teenager kids -usually used to help with brake-issues - did help to put some weight in the Fiat during the work ( with moderate enthousiasm))


groeten, Geert.

[kkemerait]

Found UNLADEN alignment specs for 1978 vehicles in a FIAT service bulletin... Hope this helps

UNLADEN 1978 124 Spider:

FRONT:

TOE: +.157 to +.314 (+4 to +8mm)
CAMBER: -0*20' to +0*40'
CASTER: +2*40' to +3*40'

Also have unladen figures for 1978 128 Sedan, X1/9, 131 2-4 door if anyone is interested.

[kensmith]

Found UNLADEN alignment specs for 1978 vehicles in a FIAT service bulletin... Hope this helps

UNLADEN 1978 124 Spider:

FRONT:

TOE: +.157 to +.314 (+4 to +8mm)
CAMBER: -0*20' to +0*40'
CASTER: +2*40' to +3*40'

Also have unladen figures for 1978 128 Sedan, X1/9, 131 2-4 door if anyone is interested.

Not sure about the symbols for camber and caster? I know the * indicates degrees, but not sure what the 20' and 40' mean? But thanks for the information!