I would cover the inside of the wheel arches with either black or full white. The way it is now, the black sticker is too streched and looks blurry.
I would also change a little bit of the black/white stripes. The round shape in the middle is not very visible from the sides, and it makes the top view weird with one big black lines although the others are regular. Maybe try to do the round shape bigger so it really appears, or just do lines ?
Also, why not use the lines pattern on the purple part ? Not with something contrasting, but with two slightly different tone of purple ?
I know, it is easy to say, and difficult to do, especially on prototypes !