Not too bad. You definately need to lay off the extreme shutter speeds. It creates absolutely no sense of speed and no blur. If you look at the rims in every shot they are just frozen. You can always add blur in photo editing programs but it is a fairly advanced technique and you are better off just using the natural blur from GT4. It also doesn't help that the rims aren't the strong point of Polyphony's great 3D renders. So it's encouraged to have some blur in your photos. Also in the 5th photo down, try not to have ugly poles in your composition, it just basically ruins the photo. The only photo I'd say is good would be the first one. It can be reworked into something awesome. Try those tips I gave you and see what you come up with next time. Sorry about the harsh criticism, just giving good advice .
They are definately getting progressively better. Keep working on them. Definately bump up the brightness alittle more and play with contrast. Other than that those have some nice angles and overall nice shots.