Swapping cars during a meeting?

[The Colonel]

Perhaps 'changing' is more accurate than swapping..........

I have not yet read the BRCA rules and regs so the answer could be there:

In a meeting with four heats and a final, can I assume the same car has to be used for all five races? Or can a driver qualify with one car and then run the final with a different one which could be more suited to changing conditions on the track?