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1949 Ford Coupe RESURRECTION
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As long as both wheels/tires are at the same elevation relative to the frame, they see zero forces. There is no reason to be concerned unless the job of fabrication is of a really crappy quality.
 

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Old(s) Fart
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As long as both wheels/tires are at the same elevation relative to the frame, they see zero forces. There is no reason to be concerned unless the job of fabrication is of a really crappy quality.
This is not correct. The suspension arms move different amounts when you corner. This not only twists the sway bar, it also pushes up and down on the ends. It's the pulling down that you care about.
 

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the 'Duracell Project'
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the question is ambiguous. sway bars basically mount 2 different ways: sway bar on axle or sway bar on frame. the brackets and links can vary greatly. at least give us an idea/pic/sketch of what your doing
joe is correct. cornering with a sway bar, the bar will twist in torsion with one link pulling down and one link pushing up equally. i do know that if needed, you can heat and bend the existing bends without affecting the torsion. i had to heat and bend the trans am sway bar to avoid my 58 truk frame. still works
 

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1949 Ford Coupe RESURRECTION
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1,050 Posts
Well, to those who have disagreed with my statement, please read it AGAIN! I said "relative to the frame" NOT RELATIVE TO THE GROUND.

OF COURSE there are twisting/up/down forces on the brackets and wheel/axle attachments as centrifugal forces are experienced by the vehicle in turns/cornering..

Simple logic would tell anyone that any modifications to mounting should pretty much replicate or duplicate stock mounting techniques.

Please brush up on your reading skills.
 

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I have a situation where the sway bar mounts must extend out about 3 inches. Question is: how stout should the mounts be? How much weight will the mounts see?
Front or rear ,straight axle or independent , frame mounts or axle mounts ? Need more info , pics possibly to give an answer , the mounts have to withstand the max force that the weight of the car can apply + shock ( impact) load ..
 

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Discussion Starter · #10 ·
Here's a pic of the mount. rear of course. Supporting plate is welded to the bottom air bag mount. A total of 3 inches sticks out from the bottom of the air bag mount. Plate is 1/4" and gusset is 3/16". In a corner body roll will exert some downward force on the mount...how much is what I'm asking. Normal everyday driving and not autocross!
 

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Are you saying that your frame is too short and the pivot point would have to extend past the oem frame? Or the pivot point is 3" inboard of the frame? Are you talking about the axle connection?
The force on any one point would be split among all 4, although at any given time they would be opposite directions.
I replaced a 3/4" diameter bar that had no frame connection, both hard points were on each lower A-arm. I changed it to a more traditional sway bar with a 1" diameter. It required the pivot bushing where it crossed the frame, with a standard bolt style link. My problem was the pivot bushing didn't line up with the frame. The attachment point was narrower than the frame.
I had to make a crossmember to to mount it. I judged the force by the size of bolts on the pivot bushing brackets. Most are 3/8" fasteners. I used a piece of 2x4x3/16 tube to cross the frame, drilled and tapped bolt holes for the brackets. With 1/4" thick plates on the tube ends extending upwards and bolted to the frame web and at the tapping points.
Not light weight by any means. Most things are engineered with a 2 to1 failure level. In other words, they take their best guess, and make it twice that strong. Safety items are 3 to 1.
 

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1949 Ford Coupe RESURRECTION
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Oh wow. Too bad you didn't post the picture on your first post. It doesn't seem that you considered the twisting motions on that bottom bracket nor any rubber/neoprene bushings (if you did, I don't see them) to dampen road noise and allow things to move around on those welded brackets. I would be concerned about the weld joints at the bottom failing due to metal fatigue because of constant twisting. Unless, the bolts are going through heim joints. Otherwise, looks cool.
 

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It looks workable, may be noisy as '49 coupe mentioned, I see 2 brackets welded to the axle, but only one under the link connection. Unsure of it's structure blocked by shock? mount.
Geometry looks OK.
My only suggestion would be to beef up the portion that extend rearward and extend gussets diagonally downward from 9 o'clock on the axle to a point just in front of the linkeye.
If I was starting from scratch, I think I would use a piece of 2x6x1/4 tube and cut out a radius to fit the axle. Then you can use the waste pieces to box in the notch. The end result is the same. Just a cleaner look. More work.
 

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1949 Ford Coupe RESURRECTION
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MGK is correct. Maximum torque is at the weld joints on the axle housing. Welds don't look that great, no offense,, but that joint on the axle housing surely needs to be beefed up. I missed that before.
 

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1949 Ford Coupe RESURRECTION
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1,050 Posts
It's pretty difficult to predict performance without some pretty deep mathematics.

Another thing I'm kind of curious about thats for the OP. I wonder why he didn't just find a conventional sway bar of the appropriate length with conventional links and bushings??? Also, though I guess it's not that important, but is the car a daily driver, a street rod, a rock climber, a circle track racer, a gasser, a rice racer, or???
 
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