Track shut down length

[quick]

Is there a hard and fast rule for the shut down length of a track Specifically, can a quarter mile strip of concrete support an 1/8th mile track or even a 500 ft. track Are 500 ft. tracks sanctioned by NHRA

[nitropimp]

We would like to see a minimum of 1/2 mile shut down for a 1/4 mile track; remember TF bikes are running 180-200 mph @ 1/8 mile.