I have 1957 ford Custom 300, it has a large turning radius.
Turning a simple corner requires a lot of room. Radius should be much tighter. Wondering
if a worn idler arm and drag link would cause this or possibly a worn steering box.
Yes on all 3, but you should also have other steering problems if it is worn that bad. Has the car been modified to ride a lot lower than stock? It is possible that the steering box has been changed to a short travel unit so the tires wouldn't rub the inner fenders during a turn. You should also check and make sure the frame is not cracking where the box is mounted, that too will change steering geometry. Also changing the length of the radius arm can shorten the travel. You never really know what has been done during it's life until you get right in there and start looking.
Turning radius cannot be adjusted on these old cars. Problem is not the turning radius but the long wheel base that you are probably not used to. You need to swing wider on corners than with a modern car.
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