well, play them slower.
then I lose effect of the piece.
What competition is this? If this were the Van Cliburn, someone might complain. If the competition was smaller, I wouldn't worry about the length of the piece. I think the 5 minute rule is just to give you an idea of how much music the competition wants. It's not like you are performing a piece that's only 2 minutes long. In my opinion 4:40 is fine. In reality, you might actually play the piece even faster during the competition - due to anxiety, nerves, etc.
Check and see if the judges are down with 4:40