About curiosity, my Marshall is very explorative! Especially when I am handling him. He's also pretty adventurous in his cage as well, normally late at night and early morning. His little "adventures" only last about 10 min, 20 at the most. All through the day he is hiding though, unless he is thirsty or switching hides. I think it depends on the snake, my guy is very brave!
As for car rides, I have heard of people taking their big boas on car rides. Actually one person had a boa who actually liked putting its head out the window like a dog.
I am not experienced so don't take my word on this.
Sent from my iPad using Tapatalk