What type of blue material are you using, blinn? If so, you can make the car look more like metal by turning down the "Eccentricity". You can find it my going to the blue color node in the attribute editor and it will be under the Specularity section. That will make the light reflection more confined and less spread out on the car.

I'm going to post a link here shortly of another post that has a really great car rendering. I think you'll be able to get some excellent tips from it.