Fabricated A-Body spindle ideas and discussion
To be clear, I'm not suggesting he has the better plan. It was the idea of roll couple that made me wonder if I was missing something.
No, I set the caster and then found the perpendicular location and set the UCA inner pivot at that location. This was based on what Mike Martin wrote in his book.
Here is a picture.
This is why I said that I think caster impacts the geometry. What I didn't try and take into account is how the front and rear pivots move in and out (if the stock adjustments are used) and this would create a pivot that is out of plane with the LCA. But I ignored it because it made my head hurt. :D
I am hopefully within a 1/16"? Tape measures and eyeballs.
I used the bottom of the frame where the k-frame mounts as a datum and measured up from there to the outer edge of the bushing on both ends. The rear measurement was harder since the frame slopes away at that point so I had to try and maintain the plane.
I had a loose k-frame to grab measurements off to try and locate the inner pivot for the LCA. And then I used 13" for the LCA length which I admit was a bit of a swag as I didn't have a LBJ to bolt in and measure to.
The other thing to note is that it doesn't seem like the bottom of the frame is level with the ground, but the slope of the torsion bar (in my case) was the same so I assumed that the suspension would effectively be 90 degrees to that plane. But it was an assumption.
Hmm...pretty different. I wonder if my LCA length is way off. It was a best guess (see above).
I will say I am pretty comfortable with my "X" dimension for the LCA inner pivot since the factory frame dimensions says 24.46" overall.
I am showing the roll center in my image above at 6.6873". Am I misunderstanding you?
To be clear, I'm not suggesting he has the better plan. It was the idea of roll couple that made me wonder if I was missing something.
No, I set the caster and then found the perpendicular location and set the UCA inner pivot at that location. This was based on what Mike Martin wrote in his book.
Here is a picture.
This is why I said that I think caster impacts the geometry. What I didn't try and take into account is how the front and rear pivots move in and out (if the stock adjustments are used) and this would create a pivot that is out of plane with the LCA. But I ignored it because it made my head hurt. :D
I am hopefully within a 1/16"? Tape measures and eyeballs.
I used the bottom of the frame where the k-frame mounts as a datum and measured up from there to the outer edge of the bushing on both ends. The rear measurement was harder since the frame slopes away at that point so I had to try and maintain the plane.
I had a loose k-frame to grab measurements off to try and locate the inner pivot for the LCA. And then I used 13" for the LCA length which I admit was a bit of a swag as I didn't have a LBJ to bolt in and measure to.
The other thing to note is that it doesn't seem like the bottom of the frame is level with the ground, but the slope of the torsion bar (in my case) was the same so I assumed that the suspension would effectively be 90 degrees to that plane. But it was an assumption.
Hmm...pretty different. I wonder if my LCA length is way off. It was a best guess (see above).
I will say I am pretty comfortable with my "X" dimension for the LCA inner pivot since the factory frame dimensions says 24.46" overall.
I am showing the roll center in my image above at 6.6873". Am I misunderstanding you?