Is it permissible to give food or money to the poor on the occasion of purchasing a new car, or is a sacrifice (dhikr) obligatory, and is it permissible to give it out some time after the purchase?

It is permissible for someone who intended to give something to the poor or made a vow to that effect, to give them food, money, or to slaughter an animal for them. If no specific time was designated for this, then there is no harm in giving it out some time after the intention was made, because the word "something" is general and includes all that was mentioned and more.