how are your front wheel bearings any play does it go away depending which way you turn? how about your axle u joints. are they all rusty and hard to move or real easy to move ?[addsig]
Could be a wheel bearing allowing the camber to change when in a hard turn. Or a bad ball joint. With a front tire off the ground, shake the tire by holding at 6 and 12 o'clock and then at 3 and 9, see what you find.[addsig]