It will be a bit difficult to talk to your dad to allow you to ride in the car with your boyfriend without him around. However, you can try telling your dad that your boyfriend is a qualified and experienced driver and that you will be very careful with the car and you will not mess around in it. Just try as much as possible to win over your father's trust.
I don't think it has anything to do with how good of a driver he is. Your dad was once 17and he knows whats on your boyfriends mind much more than you do. I know it's hard but listen to him. He is doing it for your sake.