It is typical for RC fanatics to modify their stock car based on the event that the RC will join in. For me, since I am fond of street track racing, I usually modify the body of my RC electric motor. To do so, the consideration is usually the weight of the car and the tracks that I am to race. When it comes to its weight, one need not to overdo it since it will only cause a terrible driving control and if it’s under modified or just plain stock, you can expect your RC to run as it is or way slow than what you can expect.
In modifying its engine, it usually depends on the type of power you are using. See and check first if you are into the gas powered one or the battery type since application differs. With the gas powered, considerations are to be made with the type of engine you are to use. And with the battery type, the consideration is the motor that it uses. The electric type is dependent of the coils of the motor. More coils and gear motor quality are usually the basis to assess if the motor will be working base on the power you wish having.