Originally posted by ybo1
they do not carry the impression of speed
That is still better than the impression of a photographer unable to focus. You probably didn't have the opportunity to select where you set up your camera and you probably didn't have time to practice your panning at the same spot a hundred times either. So you make the best of what you have available. At 1/1000 second you would have had lots of motion blur on the tires. At least you had an unobstructed view of the track, no metal mesh or barriers in the frame. If you do get the opportunity to select your location at another race, try to get further away from the track (so smaller movements with your camera produce more motion blur) and try to take pictures perpendicular to the track to enhance the effect. A wider aperture for a shallower depth of field will also help. Or digitally blur your backgrounds. Otherwise, you might as well buy a lottery ticket, because your odds are better.