When you have a constructor but don't want to keep creating the same object, all you have to do is add parameters to the constructor the following way:

var Car = function(wheels, seats, engines) {

  this.wheels = wheels;

  this.seats = seats;

  this.engines = engines;

};

Now you can pass in arguments when you call the constructor. var myCar = new Car(6, 3, 1);

This will result in:

{

  wheels: 6,

  seats: 3,

  engines: 1

}