[Quicksilver]

Something is slipping. A camber bar helps while the car is in the corner. Once it is out of the corner the only way it would effect anything is if the chassis is so toasted that it was yielding (permanently bending) under the cornering forces.

The two things I would look at is if the rack is moving/slipping from side to side or if the steering column/u-joint/rack connection is slipping some how. Something is moving under force so it needs to be straitened out before something bad happens.