Long arm wheel alignment

[NOAZ longshot]

I have a SandLimo sand car, and broke an inner tierod heim joint.  Now that it is replaced, I am curious what alignment specs people are running.

Camber, Caster and Toe.

FYI, I am running 33x10.5 tires on all four corners

Thanks for the help.

 

[NOAZ longshot]

Well there you go.  With a little more searching in here, I found the manufacturers suggested alignment.  Thanks Joe Fab.

1/2" Toe-in

3/16" neg-camber

10* Pos caster

 

[L.R.S.]

Always best to get the base numbers from the builder whenever possible. If you want to go a step further pull the shocks off and cycle the suspension full droop to full bump. See how much bump steer you have and make adjustments to eliminate as much as possible. Very time consuming but well worth it. 

Another option is to use a set of toe plates. One of the best tools I have for alignment on off-road cars. My set was made by @punkur67

 

[Bobalos]

Always best to get the base numbers from the builder whenever possible. If you want to go a step further pull the shocks off and cycle the suspension full droop to full bump. See how much bump steer you have and make adjustments to eliminate as much as possible. Very time consuming but well worth it. 

Another option is to use a set of toe plates. One of the best tools I have for alignment on off-road cars. My set was made by @punkur67

View attachment 30783

Im confused by this picture.  why are you going "across" with the tapes???

 

[AlpineFunco]

Im confused by this picture.  why are you going "across" with the tapes???

I'd guess this is done to make sure the steering wheel is at dead center and to find the midpoint of the car. But this I just a guess as I know nothing about aligning cars.  :classic_laugh:

 

[Bobalos]

I'd guess this is done to make sure the steering wheel is at dead center and to find the midpoint of the car. But this I just a guess as I know nothing about aligning cars.  :classic_laugh:

that would make sense, but I would think in an off road car, close enough would be close enough....  my car does not go the direction the wheel or tires are pointed anyway.  LOL.

 

[L.R.S.]

Im confused by this picture.  why are you going "across" with the tapes???

To make the front end square.

 

[Sausage450r]

You measure corner to corner to assure “square” like lrs said. 

Basic fabrication/construction technique. 

You can make things parallel by measuring straight across, but parallel doesnt mean square (90*). You do this when hanging doors and windows too

 

[Bobalos]

what are you adjusting like this?  Toe?

as a super simple example: If the car has 0" toe and there is no stagger, the measurement across the front and across the rear will be the same measurement.  if thats the case, then isn't the diagonal measurement going to be the same? 

Lets say in my example the front and rear measurement is the same, but the diagonal measurements are not, what would I adjust to fix that?  would I adjust it to make the diagonal measurements right?

thanks

Bob

 

[Rockwood]

what are you adjusting like this?  Toe?

as a super simple example: If the car has 0" toe and there is no stagger, the measurement across the front and across the rear will be the same measurement.  if thats the case, then isn't the diagonal measurement going to be the same? 

Lets say in my example the front and rear measurement is the same, but the diagonal measurements are not, what would I adjust to fix that?  would I adjust it to make the diagonal measurements right?

thanks

Bob

There's always some ackerman, so this method will assure zero toe with the wheels square to each other.

That being said, the only it does is make sure the wheels are square relative to each other, not the chassis and rear tires, which is generally more important anyway.  For that, you need string and some bar:

https://motoiq.com/wrench-tip-how-to-do-your-own-alignment/

 

[Bobalos]

when I did drag racing, we would string it to the floor & then either assume the alignment was ok & make changes as needed or take it somewhere & have it done on a rack.  but........... those cars done have any travel compared to a buggy, so it was pretty easy. 

as I recall it, Ackermann is when I turn the steering wheel say 1/4 turn the "inside" tire turns "more" than the outside tire, because the outside tire travels a larger distance so the idea is to keep the turning radius longer to account for the distance between the tires. 

that said, if the car is stationary & both wheels are near 0* relative to the direction of travel, Ackermann is not involved @ all.  Am I wrong????

 

[Rockwood]

when I did drag racing, we would string it to the floor & then either assume the alignment was ok & make changes as needed or take it somewhere & have it done on a rack.  but........... those cars done have any travel compared to a buggy, so it was pretty easy. 

as I recall it, Ackermann is when I turn the steering wheel say 1/4 turn the "inside" tire turns "more" than the outside tire, because the outside tire travels a larger distance so the idea is to keep the turning radius longer to account for the distance between the tires. 

that said, if the car is stationary & both wheels are near 0* relative to the direction of travel, Ackermann is not involved @ all.  Am I wrong????

Correct, but if you're at all off-center, the wheels won't be square (straight ahead) and crossing the tapes rules that possibility out.  Otherwise, it's possible to have "zero toe" with the wheels pointed into the canal.

 

[Bobalos]

Correct, but if you're at all off-center, the wheels won't be square (straight ahead) and crossing the tapes rules that possibility out.  Otherwise, it's possible to have "zero toe" with the wheels pointed into the canal.

But if nothing is referenced to the car, then I dont see how it is actually going to tell me anything. 

Smells like its time for me to play with it & see if I cant figure out what your saying.  string, a plumb bob & some tape, taught me more than any book ever did. 

 

[Rockwood]

But if nothing is referenced to the car, then I dont see how it is actually going to tell me anything. 

Smells like its time for me to play with it & see if I cant figure out what your saying.  string, a plumb bob & some tape, taught me more than any book ever did. 

Nope, other than your front pair of wheels aren't arguing with each other.  Alignments should be done for the wheels relative to the chassis, but for a sand car, pointed mostly forward is generally fine, LOL

EDIT: Toe wise.  Caster has a lot to do with stability and feel.  6* is the minimum for going fast.  10* preferred.  Each chassis is different, so make sure to cycle the suspension as mentioned above to make sure everything is happy.