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Discussion Starter · #1 · (Edited)
Here is a pic of how the previous owner did the steering arm on my '57 gasser. The car has a bit of bump steer, I'm in the process of eliminating problems one by one and wondered what your ideas were with this please? I'm of the opinion after looking at different cars and collecting information from fellow enthusiasts that the arm should run paralell to the ground. Thoughts please.
Micky T.


From another angle...

Please note: A lot of work has been done already under there and it doesn't look as untidy now as in the pic.
 

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What you want here is for the steering not to be "steering" as the suspension moves up and down.

My first thought is that the pitman arm and drag link attachment location is a lot worse than the drag link attachment and steering arm.

Here's why: the drag link length is short compared to the distance from the axle to the rear spring eye. So when the axle/spring moves up or down, the short drag link is going to steer the car to the right when that happens. You can minimize that by making the drag link parallel to the ground when the car is sitting, steering wheel straight ahead, and the full weight on the front end. That might mean raising or lowering the connection at the steering arm - in other words a different shape to it, or some kind of spacers.

Looks like it's down at the front, but you don't have the engine in it yet either, so it will get better.
 

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"Rick, Take another look, I believe I see an engine in there"

Well you're right, that just makes a bit worse. It's going to steer right when the suspension extends and steer left on a bump.

But maybe there's a bit of weight to be added yet.
 

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those look like early 50's late 40's chevy spindles? go online and check out SPEEDWAY MOTORS selection of steering arms. mount it at the UPPER bolts. That should help ALOT, not a cure for total eradication of bump steer. but ALOT BETTER.
 

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You've got two things working against you. One is the shortness of the drag link. The other is that it's not parallel to the ground. I would make a new drag link with a Z or a drop in it. This would help alot.
Rick
 

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Can I raise the front and lengthen the arm to lower the rear, a combination of both?
I would not lengthen the pitman arm unless I could find a longer one somewhere... Something about cutting and welding on steering components just scares me... I would also loose those spacers between the axle and spring and look for springs with more arc...
 

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Can I raise the front and lengthen the arm to lower the rear, a combination of both?
if you lengthen the pitman arm, (the one on the steering box), YOUR arms will have to become much stronger, but on the other hand the steering ratio will be quicker !!
 

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Discussion Starter · #12 ·
The steering arm from the steering box has been shortened already by the previous owner (just out of shot in the pic), that's what gave me the idea of sourcing a newer/longer one. The square tubing has been boxed for added strength and new shackles, bolts etc added to hold it all in place securley. I agree that different springs with a better arc would be better and no doubt will have in the future, but having said that; what about this pic?


There's is a good turning circle on the car, I've seen them sometimes have to do a 5 point turn to get out of the drive way, so if making the arm longer gives me a quicker turning ratio of the steering wheel then I would have thought that a bonus?

I love all the input, many thanks, I've learnt and still learning so much from this forum.

Micky T.
 

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A Zee or drop won't help, you need to raise the front joint as gary said.
I disagree. I have seen it done many times with good results. However after looking at the pics again it looks like it may be possible to bend the arm comming off the lower spindle up which would help in making the drag link level. Having the link level or both ends level with the ground and connected with a diagonal piece or a Z is what your looking for. If it was me I would go back to the original steering box and use cross steering.
Rick
 

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I disagree. I have seen it done many times with good results. However after looking at the pics again it looks like it may be possible to bend the arm comming off the lower spindle up which would help in making the drag link level. Having the link level or both ends level with the ground and connected with a diagonal piece or a Z is what your looking for. If it was me I would go back to the original steering box and use cross steering.
Rick
I agree with Rick. Z'd drag links are done on lifted solid axle 4x4 trucks all the time. Same principle as in this situation.
But, still not as good as a crossover steer IMHO.
 

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Rick_L is correct, changing the shape of the drag link does not affect the geometry of the steering. It's the location of the ball joints on the pitman arm and on the steering arm that determine that. I've also seen "Z'd" drag links, but that does not change the geometry. As the suspension articulates this geometry setup will push or pull the steering arm, steering the front wheels, without any movement in the steering wheel. Changing the shape of the drag link will not change that. I have nearly 50 years as a mechanical engineer and as a mechanic on my own rigs, and I'm completely certain about this.
Aloha,
Willy

BTW, I' m fighting this problem on my 4x4 55 truck right now, changing it to a cross steer to get rid of the bump steer problem, which is somewhat like the one above. And, I did my own gasser as a cross steer for that same reason. Neither is on the road yet, but I think I will be able to completely eliminate any bump steer problem by doing this.
 

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Actually you can have the same problem with some cross steer deals too, except that the link is usually longer so it won't make as much difference. There are also ways to do the cross steer that will reduce the problem or eliminate it.
 

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steering arm length ?

I am not a engineer or anything like that but if I am thinking correctly changing the pivot location by lengthing the steering arm will increase the overall steering ratio dramaticly. The only steering I know of that works with a long arm is in a sprint car. I really think he needs to move his steering box down about a foot and add u-joints to hook to steering column. With a faster steering the car will feel nervous and twitchy or jumpy.
P.S. Since you asked I wouldn't drive that Willys across a parking lot let alone down a race track.
In "67 I hit a pot hole in a race track at speed ( a WW2 bomber plant) that would have killed that front end.
I believe anyone copying this design is looking to get a Darwin Award. :anim_25:
 

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All this talk of "Cross Over" steering.

Are you guys referring to the steering box pitman crossing over to the pass spindle, then a center (drag) link crossing back over to operate the driver side spindle?
 
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