Stepping Outside The Box

O

OriginalRamcharger

Guest
This is just a little teaser for experienced dragracers. As you walked through the pits, you saw more than a few ladder bar cars.These cars have, of course, two sturdy ladder bars that are attached to the axle housing and which pivot at their front attachment points. Okay, here's the question. All the ladder bar cars you saw had two ladders. Now, have you ever seen a car with only one ladder? I'd venture to say, if you're of any age at all, you've seen hundreds of cars with only one ladder. Don't you remember? Okay, here's the answer. Consider the tube which surrounded the driveshaft on the early Fords and Chevys. Wasn't that firmly attached to the axle housing and didn't it pivot at the front? Of course it did. It was a single ladder bar. You could do the same sort of thing with an open driveshaft. Just attach a single ladder at the side of the driveshaft. Which side? Well, if you'd like to cancel the unloading of the right rear, you'd want it offset to the US passenger side. How much offset? If you offset it by the wheelbase divided by the axle ratio, you'd be pretty close. Sorry to disturb you. I just enjoy nudging people outside the box.
 
Dirt cars been running that set-up since the early 80's. You need to find another box, that one is full...:owquitit:


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Interesting, but that's not quite what I meant. To liken that to a dragracing ladder is quite a stretch. The front is obviously sprung, which is a long way from a pivot. Again, it's interesting, but I was trying to point dragracers toward the old Fords and Chevys.
 
OriginalRamcharger said:
Interesting, but that's not quite what I meant. To liken that to a dragracing ladder is quite a stretch. The front is obviously sprung, which is a long way from a pivot. Again, it's interesting, but I was trying to point dragracers toward the old Fords and Chevys.
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I know what you are referring too. Nascar still runs truck arms. You could remove the shock in the above example and connect bar directly to chassis with some sort of pivot. But a 4 bar set-up does the same thing. Instant center.
 
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I'm a little surprised how many ways people have tried to do the same thing. Without birdcages at axle tube it's gonna bind creating inconsistancy.
 
StandOnIt said:
That is a wish bone rear end. Sheesh.
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You're obviously not ready to "step outside the box." Yes, you have the common name, but look at it again. Isn't it also a "bar" rigidly attached to the rear axle housing and pivoting at the front?
 
I'm certainly not criticizing your suspension. I've seen many like this and that's fine. I'd just point out that there might be an easier way. If you eliminated that short vertical link at the front of that long centrally located "arm" (just pivot the arm at the front) and also eliminated the two lower arms and then added a Panhard, you'd end up with the same geometry as the early Fords.
 
OriginalRamcharger said:
I'm certainly not criticizing your suspension. I've seen many like this and that's fine. I'd just point out that there might be an easier way. If you eliminated that short vertical link at the front of that long centrally located "arm" (just pivot the arm at the front) and also eliminated the two lower arms and then added a Panhard, you'd end up with the same geometry as the early Fords.
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If this is superior why did it disappear when somebody figured out u-joints?
 
By no means is it superior! I was merely pointing out that a ladder bar car really needs only one ladder. We know this because Detroit used one ladder cars for years. An open driveshaft simply allows the benefits of additional links.
 
OriginalRamcharger said:
By no means is it superior! I was merely pointing out that a ladder bar car really needs only one ladder. We know this because Detroit used one ladder cars for years. An open driveshaft simply allows the benefits of additional links.
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Take a ten foot 2x4. Put end against something that rolls and start pushing it across the floor. Impossible to go in a straight line huh? THAT is why ONE ladder bar and no other links won't work. Like pushing a rope. You need a triangle to keep the rear end centered. Panhard rod won't do it.
 
KTMLew01 said:
Take a ten foot 2x4. Put end against something that rolls and start pushing it across the floor. Impossible to go in a straight line huh? THAT is why ONE ladder bar and no other links won't work. Like pushing a rope. You need a triangle to keep the rear end centered. Panhard rod won't do it.
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It's a RIGID connection. That rigid connection could very well take the shape of a triangle.
 
KTMLew01 said:
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This was king of the drag strip for decades. Not sure what they are doing now.
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It's a 4link, which is the most common arrangement with winning cars at the dragstrip. I've never attempted a survey, but I'd guess that the second most popular setup is the ladder bar. I was merely pointing out that ladder bar cars commonly use two ladders, whereas only one is actually needed. A variation of the 4link (not nearly as popular, but having the capability of eliminating the unloading of the right rear on launch) is the 3link, where the upper left link is eliminated. The 3link has the disadvantage of unequal loading during braking. Considering that the C-Type Jaguar won at Le Mans with a 3link, this is not a severe limitation.
 
Sure is! A competition car...done right...is a beautiful thing to behold. I remember taking a walk through the place in California where the competition Nissan cars were built about twenty years ago. I couldn't get over the appearance of the TIG welding of the tubing. Absolutely beautiful! Take a look at "Flying Shingle" in YouTube. This is the Ken Miles competition MG. Beautiful!
 
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