This is a tricky one. I've taken photos in Daytona for the 500, and it becomes a game of shutter speed vs exposure. Too fast a shutter makes a dark picture with no blur in the cars, and too slow makes a brighter picture, but you can't make the car out. Depending on the day and amount of sun, spend a little time adjusting your ISO, shutter speed, and f/stops until you get it right. Second issue is keeping a steady camera if you're looking for little or no blur around the cars. If the cars are moving, you are moving with them, while trying to keep a car in the lens to get the shot. For what it's worth, on a sunny Daytona 500 I use ISO 100, 1/200-250 shutter speed and f/8 as a starting point. I keep a CPL, ND4, and lens hood closeby incase the situation requires it. It would have to be really bright with a slow <1/100 shutter to need the ND or hood. Good luck and have fun!