I plan on purchasing my son a nice car even though his mother asked me to not.
What is the point in you going against his mother's wishes?
I'm rich and I can give him whatever he wants.
That's good that you don't have money problems, but it's it's important to teach your children the meaning of a dollar. If they get things to easy they won't learn how to work and save for the future.
I'm going to buy my son a couple of very nice cars. He doesn't need to know that I'm spending a small fortune on them.
Just be careful not to spoil your son with these nice cars. It may be a better idea to have him to some sort of work to earn just one of them. Giving him the car for free is going to cause him to take for granted the true cost of an automobile like that.