front end question

[toml]

Help!!!
I had the upper and lower control arms replaced along with the tie rods along with the bushings.
I picked the car up and drove it home but it pulls severely to the right. If I let go of the wheel the car will make a 90deg. turn. Very scary. The mechanic said he did alignment on my car but the frame is slightly out. Might have been in a accident before I brought it. If the frame is out does anyone where can I find the measurements to check this? Can the frame get straightened at a body shop?
I mentioned this to a friend of mine he said the caster could be set a zero when the mechanic did the alignment.
The car is a 1978 fiat spider.
Thanks
Tom

[RRoller123]

The Caster can't be adjusted, it is set by the geometry of the A-arms, but the camber is adjustable with shims, and the toe-in with the tie rods. It sounds like the toe-in was not set correctly, for the pull to be so severe.

[bobplyler]

Actually, you can adjust the caster by putting different numbers/size of shims behind the two bolts holding the lower control arm.

[azruss]

If the caster and camber are off, it doesnt do any good to align it. Yes, a frame shop can fix the misalignment of the unibody. It will change your hood and door gaps depending on how bad it is. If it pulls as bad as you say it does, i doubt if the mechanic even looked at caster and camber. As mentioned, camber is corrected by adding shims to both lower a-arm studs. caster is adjusted by adding to either the front or back stud depending on what is needed. Caster should be done first. It isnt this clean of a process as you can expect the addition of shims to change both.

[toml]

It seems like everyone is saying the alignment is incorrect.
Does anyone know the spec's for my car? It is a 78 spider.
Thanks again for everyone's help.

[RoyBatty]

You could also have a problem with the toe adjustment of the front end as well as the caster and camber being off.

[RRoller123]

This is the first time reading on the forum where I have heard that the caster can be shim adjusted. The camber is set by changing various thickness shims at the red arrow, but the caster requires the entire lower (or upper) control arm to be moved forwards or backwards. Are you guys saying that this is regularly done with shims? My understanding has been that this is set by the permanent geometry of the frame and tower control arm mounting locations?

[bobplyler]

Adding shims to the front stud moves the ball joint back. The reverse moves it forward.

[RRoller123]

Do you mean adding shims say to just the point where the red arrow is, to sort of twist the A-arm orientation and thus move the ball joint a little backwards?

[81SPIDERMATT]

stock spec for camber I think is 1/2 degree positive .... plus or minus 1/2 degree ....

i am with rroller on the caster ... thought it was set and camber and toe were the only adjustable options ....

adding different thickness of shims to front or back in would indeed change the caster ..BUT this thread is the first I have ever heard it mentioned on a spider .... I don't even remember what caster spec is and I never bothered to investigate that part of an alignment as I thought it was a given .... I also know from lifting my truck and creating negative caster that positive is what you want for road manners ... and even on the truck it is not adjustable without cutting the steering knuckes off of the axle ... turning them to what you want and re-welding them in place (cut and turn)

I think what original poster needs to do is get an alignment at a shop that knows the type of suspension they are working on ..get it aligned correctly and if they can not get it into specs than post numbers of what is left to decide next course of action

my car had "sagged" for lack of a better term and needed a frame shop to correct ... they did not have the specs for the fiat and worked closely with the alignment shop to figure out where and how much to "unsagg" it ... I had a bad negative camber problem

also no one has mentioned the brakes.... could the brakes be dragging on one side and pulling the car... maybe a close inspection of that system may reveal a culprit

also an alignment should include all three caster...camber ...and toe ..tell them what you want and that you want the measurements of each .... hope some one will chime in with actual specs

[4uall]

this might help

Google is your friend

[redcars]

Caster is easily and routinely changed by adding or removing shims from just the front or back or by adding shims to the front while removing them from the rear or vise versa . This is done on most double A-arm cars not just Spiders. If you take the same amount of shim from the rear and add it to the front. You will change the caster with out changing the camber. Any change to caster or camber will change the toe so do the toe settings last.

[redcars]

Did your car drive like this be for you had it worked on. If not than your "mechanic" caused the problem.

[RRoller123]

Interesting. First time in 3 years that Caster adjustment has been discussed on the forum as far as I can remember. So I think I will take mine in and get a professional 4-wheel alignment and see what pops up.

[toml]

The shop I brought my car to screwed things up. It drove o.k. but I wanted to replace some tired front end parts with new ones. Now I need to find a good place to check what the mechanic did and do a proper alignment. It is so bad it's scary. Like I said earlier if you let go of the wheel it will make a right turn. I also got new tires. 165 hr 13 82 h I don't know if that would affect anything. I regret doing all this. Should have left things alone. But I love the car and wanted to improve things.