Ich möchte sicher nicht für Verwirrung sorgen, aber es müsste heissen:

Modified Advanced J/MA xxx (race number)

Ages 13 to 17

The eighth mile may not be run quicker than 7.90 seconds. This applies either to a dial-in of your own or heads-up. Runs from 7.70 sec to 7.89 sec. are rated as a breakout. Any racer who runs quicker than 7.70 seconds or faster than 140 km/h (87 mph) during the event, in qualifying or eliminations, will immediately be excluded from the rest of the event.