It would be better the effects where not based on the current speed. Instead make it based on the acceleration.
Remember the experience you had on the bus? When the bus starts moving, you feel a sudden force that pushes you toward the back of the bus. After a few moments, that force disappears as the bus moves at a constant speed. And when the bus stops, the same force occurs, but instead, it pushes you forward. Now imagine that you are the HUD and the bus is the camera.