More Positive Caster with Upper Control Arm

[cidhockey]

I cant get anything but negative caster with the existing setup. I even did some filing of the strut holes to gain a bit (from the side with the least caster). I am going to change my upper control arm bushings and they are threaded. The manual says to center the bolt holes on the control arm by turning the threads so 1.85 inches shows between the hole and each inner edge of the control arm. The only reason I can think of for this setup was that it was intended to allow caster adjustment. Does any one know if instead of centering the shaft if you can move it back to increase caster?
There shouldn't be any binding with the ball joint and it would not be enough to affect the spring or shock. I have seen other 60s cars that adjust caster by moving the upper control arm.

[Mr-Mach1]

I have the same problem and my car is uncomfortable to steer and drive on the open road. Wheel doesn't turn back either. On modern A-arms are the adjusting point either via a slot or shims. I'm going to shim between the front bolt and body. This will push the top of the spindle back increasing the caster. The camber and toe will also be affected so it'll have to go back to the alignment shop.

God bless
Leon

[texastomeh]

Anyone come up with a good workable solution?

Have same problem and would be very interested in hearing any updates.

Thanx,

Tom

[bbogue]

Anyone come up with a good workable solution?

Have same problem and would be very interested in hearing any updates.

Thanx,

Tom

Me too. Same issue. At speeds over about 60mph steering is "uncomfortable." Wish I could think of a better word to describe it.

Bill

[bbogue]

For the longest time I thought the caster spec for these cars called for negative caster (forward tilt). But today, in the text of part 7-1 section 2 of my 61 Shop Manual I noted,

"The correct caster angle, or backward (positive) tilt, is -1/4* to -1 1/4*." (I'm using an asterisk for the degree symbol.). In the spec section of part 7-4 this is shown as -1 1/4* to 1/4*.

I can only guess whether the negative sign was inadvertently left off of 1/4* in the spec or the range of the spec includes slightly negative caster. Certainly, the use of both the word "positive" and the negative sign is confusing, but it seems clear to me from the use of "backward tilt" in the text that positive caster (backward tilt) isn't something new to these cars, brought on by radial tires.

So, why is it so hard to get positive caster? What is different 55 years later?

Leon, I'd love to hear how your shimming for caster work turns out.

Bill

[Mr-Mach1]

Yeah, me too. I found both upper shafts badly worn . I did put a 1/8" washer behind the front bolt. Since I had the car aligned with the worn shafts who knows what the specs are now. Still trying to get my 4 wheel disc conversion sorted.

[bbogue]

Yeah, me too. I found both upper shafts badly worn . I did put a 1/8" washer behind the front bolt. Since I had the car aligned with the worn shafts who knows what the specs are now. Still trying to get my 4 wheel disc conversion sorted.

Leon,

You may be on to something by adding the washer to the front bolt. Here's a link to a discussion on improving positive caster. I don't know if it is applicable since it's concerning a mustang but the concept makes sense. There's also mention of poly strut bushings which may not even be available for our cars. I've also read that poly strut bushings can be too stiff and can actually be dangerous in this application.

http://www.network54.com/Forum/74182/thread/1272656867

Bill

[bbogue]

Leon,

Relative to your interest in more caster, here is a link to a thread that includes an increase in caster on my car.

http://www.vintagethunderbirdclub.net/p ... ter#p87182

Best wishes.

Bill