sorry, i see everyone taking mid-day sunshine pics.
not to anyone in particular...but if you're looking to get great shots of your cars....great days (ie: lots of sunshine) are the worst for taking pics, unless you're shooting in sunrise or sunset.
direct overhead sunlight is the worst lighting for the car. i wont go into the specifics...but basically you'll have harshlight coming from the wrong spot (above) and it creates "hot spots" and harsh shadows.

so go out and shoot on a cloudy day!!!!

hope that helps someone out...

 

Or use a flash to fill the shadows. I love it when people ask me why I'm using a flash when shooting at high noon.

 

^^^agreed, forgot to mention that.
yeah, its funny--for shooting shiny reflective subjects like cars.
use flash during the day, and dont use it at night
seems crazy but its true.
the flash fills in the shadows during the day but at night it just leaves a bright hot spot on the car