First thing off, did you read the guidelines for the critique forum?
One photo per member per week.
Secondly, none of your images make the grade for being an acceptable panning shot, especially since they have already been downsized from the original shooting resolution. That is because downsizing an image hides minor flaws, but the flaws in your image are still present after the downsize.
You've left no EXIF data on the images, so I can only guess at why your pictures are soft, most of the time it is because beginners get too ambitious and go for too low a shutter speed, since that is how the others do it. Well, you have to learn before you can fly, so work off the inverse focal length rule and step it down as your keeper rate increases. That means to pan at around 1/100th sec if you are at 100mm, 1/50th sec if you are at 50mm, and so on.
The second possibility is that you have misfocused, and as you are using a prosumer camera, that is understandable. So instead of using any form of autofocus (single shot or continuous) prefocus your camera so that there is no lag when you want to take the shot. It is much more deliberate than with SLR-tyle focusing systems where they can keep up better, but it is also good practice to learn the basics first.
In various forums I seee people saying that their shot is straight out of camera, no PS except for resizing, and I'm thinking, are you just lazy, or are you trying to tell the everyone how hot a photographer you are, and you don't need Photoshop like everyone else? Shooting the photo is only one half of the process, with film, the photographers had to hit the darkroom, or send it to a lab for the media to be processed, sometimes dodged and burned, while with digital, the photographers park themselves in front of the computer. It is necessary, and it has to be done, if you want to produce something you're proud of.
first of all, i think your hand moves a little faster than the vehicles itself. therefore, the images seems a little out of focus and blur. try resisting moving your hands too fast when it comes to panning. it's very important to have tack sharp subjects. you must remember to keep the pace of the vehicle your camera at the same pace.
what shutter speed are you using? i'd advice to lower the shutter speed instead. normally, i use 1/40 to 1/120 for 80-200mm. if the shutter is too fast and the vehicle is too slow (like normal cars, not race track), then you will not achieve a good panning photo.