You should try to train with other mushers so that your dogs learn how to run on the same trail with other teams. There will be times when other teams pass you and times when you will pass them. Passing can be going by a slower team in the same direction or passing when going in opposite directions, which is called head on passing. Training for races is more than going fast. The dogs will have to know how to start a race.
Some dogs are afraid of cheering people and the starting chute.
You can practice by having friends be the crowd and act out the race start and count down. Teach your dogs that it is fun to run to the finish line and the noisy crowds. Another skill sled dogs need to learn is how to travel. Mushers with big teams have special dog boxes put onto trucks and travel in a mobile canine condominium from race to race. Your team can easily ride in airline crates or cages in the back of the family station wagon, but they must learn the routine of riding in the car, stopping briefly at rest areas and eating and drinking while away from home.