Dublin Motor Speedway in Dublin, NC has altered its purse payoffs for the 2015 racing season.
Weekly top pay will be as follows:

LLM - $1000 to win
OWM - $1000 to win
Super Street - $525 to win
Pure Stock - $300 to win
U-Car - $250 to win

My understanding is that these purses will be paid no matter the car counts in each class. You might give promoter Richard Bailey a call to verify.