That depends, you running in the elevens?
here is link to the rules for Bradenton motorsports park. sounds like anything fast than 13.99 needs a helmet. these are the test and tune rules, which i am sure will be in place
What they really recommend is wearing a helmet if you car is 13.9 or faster if you dont have one, tell them to put a n/t and they will more than likely let you go, if your car is faster than 11.50's i believe they want you to have a cage/ partial cage but they also might let it slide. Of course if your car is 12's or faster they are going to tell you to wear a helmet.