[TimG]

On the same note, the owner of a car is not asked if the engine is a restamp or if it is the original motor. No ask, no tell. I don't know of anyone that would volunteer the fact that their engine is not the original one and any word of mouth isn't supposed to influence the judges. That being said, a judging leader may recommend that a car be removed from judging rather than move forward with the process.
If the judges are certain that an engine is not the original stamp, they may convey this to the owner and offer them the opportunity to withdraw the car rather than have it put in writing that the engine is not typical factory production. This holds true for an even worse offense, the trim tag or VIN plate.