The new rules are out for judging home built racers. Factory built racers are not included in this. In order to be judged the machine must be 35 years old. You must have documentation (and there are different types asked for) that they were operated in a contest of speed, acceleration, or handling in the period of their manufacture. There are a lot more things involved in documenting a competition machine but this is the basic rule. So if someone builds a new racer from parts today it won't be eligible for judging.