It’s called bracket racing. Each racer takes their fastest qualifying time and uses that as a base. So if one guy qualifies st 10sec the other at 12sec then when they face off in a race the slower guy gets a 2 sec head start. The key is don’t run faster than your qualifying time or your out. Hence the name bracket racing. You want to stay as close as possible without going over beating your opponent then you advance until your the last one. Then Victory!!