Setting Caster On 36 Fordor

[Jack Jenkins]

I am installing a 5.0 with AOD. I have removed the X frame and split the front wishbone. I am in the process of heating up the wishbone shackle eyes. I removed several of the springs so will I need to bend the eyes down to get the proper caster?

Thanks.

Jack

[TJ]

Caster is set by the angle of the wishbone not by the spring.

[Ol' Ron]

The bracket that mounts the end of the wish bones should have slotted holes so the castor angle can be properly set. Also the size differance of the front to back tires. I set ny caster at 6 degrees
Gramps

[V8COOPMAN]

Originally Posted by Jack Jenkins

I am installing a 5.0 with AOD. I have removed the X frame and split the front wishbone. I am in the process of heating up the wishbone shackle eyes. I removed several of the springs so will I need to bend the eyes down to get the proper caster?

Thanks.

Jack

Hey Jack ..... I wish you had asked your question before you split the wishbone. I can see where you would think that changing the angle of the spring leaves would change the angle of caster, but the caster (of the AXLE) is actually going to be changed by the UP/DOWN movement of the REAR end of the split wishbones.

Guys normally DO have to bend the shackle eyes after splitting the wishbone, but it's not to adjust for caster. When you split a wishbone, the REAR ends are normally spread apart and mounted in the area of the frame rails. What this does is move the shackle eyes TOWARD each other, which drastically changes the dimension for the length of the main spring leaf. In that case, you need to heat and bend the shackle eyes OUTWARD to maintain the original dimension between the two so that the original main leaf can be utilized.

In the case of what you are doing, the normal approach would be to first measure the distance between the spring eyes on the wishbone. Then, split the wishbone and mock-up your intended situation by setting the axle/wishbones assembly under your chassis rails with the REAR ends of the wishbone now spread to their respective mounting locations. Now you will be able to see how much the FORWARD ends of the wishbone have moved TOWARD each other. At this point, you would heat and massage the two spring eyes apart from each other to approximate that ORIGINAL dimension. You also want to massage and twist the two spring eyes to be PERPENDICULAR to the axle itself.

With the chassis sitting at approximately "ride height", place an angle finder against the front face of the I-beam to give you an approximation of the caster angle. Moving the REAR ends of the split wishbone up or down (to small degrees) will change the caster angle of the axle. If your caster is WAY-off (5º-7º POSITIVE is normal), you'll need to pie-cut the wishbones just behind the axle and adjust the angle before rewelding the two pie-cuts with your new angle. Hope this helps ya.

Coop


.

[1931 flamingo]

When I did my '32 back in the 60's I welded "bungs" into the end of the split bones and installed tie-rod ends which made the caster adjustable to the fixed brackets on the frame.
Paul in CT

[V8COOPMAN]

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Originally Posted by 1931 flamingo

When I did my '32 back in the 60's I welded "bungs" into the end of the split bones and installed tie-rod ends which made the caster adjustable to the fixed brackets on the frame.
Paul in CT

Flamingo ..... I understand welding bungs into the ends of the split wishbones. Guys have been doing that for decades. What I DO NOT understand is how extending or retracting the tie rod ends would be an effective way to adjust the caster of THE AXLE. Seems like all that would do is adjust the wheelbase dimension, as well as possibly tilting the spring pack in the front crossmember. Can you clear-up my geometric understanding, please?

Coop


.

[TJ]

Originally Posted by 1931 flamingo

When I did my '32 back in the 60's I welded "bungs" into the end of the split bones and installed tie-rod ends which made the caster adjustable to the fixed brackets on the frame.
Paul in CT

The rod ends can only move the axle forward or backward, they make no effect on the caster. The caster would be set by where you drilled the hole in the bracket for the rod ends and you need an angle finder on the axle to tell you where the hole should be on the bracket.

[Bored&Stroked]

What TJ and Coop just said . . .

[1931 flamingo]

My mistake..........
Paul iin CT

[Als48]

Coop, Ron and others,

Thanks for the great explanation, guys. I need to make the same adjustment to my split wishbone/now radius arms, as I also have re-mounted my arms a little lower, giving me a camber of around 10 deg. This arrangement makes my '48 very hard to steer while stopped or at slow speed.

Al Hook

[alchemy]

Originally Posted by Als48

Coop, Ron and others,

Thanks for the great explanation, guys. I need to make the same adjustment to my split wishbone/now radius arms, as I also have re-mounted my arms a little lower, giving me a camber of around 10 deg. This arrangement makes my '48 very hard to steer while stopped or at slow speed.

Al Hook

Not camber, you mean caster. Other than raising the back ends of the split wishbone, the only other way to fix is to slit (saw blade width) the wishbone about 95% through right behind the forged yoke, bend the very slight amount to close up the slit, then check caster and reweld.

Slit from the bottom to reduce caster. Slit from the top to increase caster.

[my4dv8]

Camber is fixed by the i beam axle and can only be changed by bending the axle. Assuming your spring is in front of the axle , when you split the bones and moved them out the spring perches still need to be parallel to the axle .Caster is fixed and non adjustable, fixed by the location point of the wish bone end.

[19Fordy]

V8 and all other camber/castor posters.
THANKS so much for your thorough explanation of this topic as it's so easy to get misinformed.

[Jack Jenkins]

Thanks for the responses.

I just got done bending that last eye tonight and got the bushings and shackles installed.

I removed 7 springs and it seems lie everything is going together good. I do have some hangers and the ends of the wishbones hanging on the frame. My caster is about 0 degrees so I am going to raise up the ends of the wishbones
and hope that will give me the 7 degrees I need.

I guess you really don't know if everything is going to work until it is on the road.

I am putting a new floor in the 36. Does any one have pictures of where the supports will go under the floor?

[V8COOPMAN]

Originally Posted by Jack Jenkins

I removed 7 springs and it seems like everything is going together good. I do have some hangers and the ends of the wishbones hanging on the frame. My caster is about 0 degrees so I am going to raise up the ends of the wishbones
and hope that will give me the 7 degrees I need.

Jack ..... NOT to criticize your efforts, but God only knows that ALL of us had to start-out by learning the basics. It seems that you are confusing POSITIVE CASTER with Negative Caster. POSITIVE CASTER will have the TOP of your I-beam axle leaning farther toward the REAR of the car than the BOTTOM of your axle. Think of it in theory like looking at the front forks on a bicycle. The forks lean toward the rear AT THE TOP. That is POSITIVE caster.

To INCREASE your POS caster toward the (+)7º that you're looking for, you would need to LOWER the REAR end of your radius rods.

BELOW is an exaggerated drawing showing both a "pie cut", as well as the POSITIVE Caster direction that you're looking for. Hoping this helps somewhat!

Coop

[Jack Jenkins]

I noticed on my first post I said I would bend the eyes down I meant out. Thanks for the correction on lowering the ends of the wishbone to get the caster.

I am going to try that first before I pie cut the wishbone.

No worry about criticizing. I have learned so much from helpful people.

thanks

jack