If you're looking to add weight to your remote control car, there are a few different methods you can try. One way is to simply add lead weights to the body of the car. This will increase the overall weight of the car, making it slower and harder to control. Another way to add weight is to fill the tires with a heavier substance like sand or gravel. This will make the car more difficult to turn, but will also add traction and stability. Whichever method you choose, be sure to test drive your car after adding the extra weight to get a feel for how it handles.