It is my understanding AMSA is going to adopt the 1000cc rule period. That being said, i think this is a typo in the rules:

Motor
The motor must be a 4-cycle motorcycle engine with 1205cc maximum, and must be self-starting by the driver while seated. Cars can only be pushed to start in case of mechanical failure with approval by Jerry Tague for that event. It must be corrected by the next event.

Jerry will need to advise.