Turning radius

[mkmskm]

Does anyone know the turning radius of a stock Model A and then a shortened Pitman arm?

 

[rglaab]

I'm not sure about the radius, but doesn't the shortened arm just allow quicker steering response? I didn't think it would change radius.

 

[160B]

shorting the pitman arm increases the turning radius.

go to this thread

http://fordbarn.com/forum/showthread.php?t=77013&showall=1

 

[Keith True]

I've never found any difference.I've installed quite a few,and always found the spindles hit the stops before and after.That has always been on 2 tooth boxes,never tried it on a 7 tooth.

 

[160B]

Visualize concentric circles, if you move the arm through a set angle the distance traveled increases as you move to a larger diameter circle, thus with a longer pitman arm the end of the arm travels a longer distance thus causing the front wheel to turn more, thus a longer pitman arm reduces the turning radius.

 

[rglaab]

The steering goes from stop to stop on our car so I don't think the turning radius would change. The stops are the ultimate determining factor for radius correct?

 

[160B]

I agree that the stops determine the ultimate turning radius. With a short pitman arm it will take more turns on the steering wheel, thus more time, to hit the stop. Thus the length of the pitman arm determines how fast you move the tie rod and thus the turning radius is affected. If the car is at a rest and you turn the steering wheel to the hard stop then the turning radius would be the same with either a long or short pitman arm. So I would say that the static turning radius is not changed but the dynamic turning radius is affected.

 

[Tom Wesenberg]

It's been years since I read the radius, but I thought it was about 33 feet to do a 180* in the road, so the turning radius would be 16 1/2', if 33 was the right figure.

 

[Preacher]

I was always told it was 17 feet. ... close enough!

 

[2manycars]

The spindle stops on the axle will determine the steering radius. I have found that shortening the pitman arm will not effect the radius, unless the arm is shortened too much. This is more true with the 7 tooth box, which has less travel then the 2 tooth. If the pitman arm is shortened no more than 1-1/2 inches, the turning radius is unaffected.

 

[Randy in ca]

FWIW the specifications section of Mac's website gives the turning radius as 17' for both the 2 and 7 tooth boxes.

 

[29ModelA]

I guess I am going to have to check our steering stops, as ours doesn't turn sharp at all....