Modding a servo

Can a servo's motor be upgraded to a heavier duty motor? I know a new case would need to be made forit because the motor i want to use is bigger than the servo itself but is it possible?

I wouldn't think it's worth it - you'd have to upgrade the gears too, so you may as well just buy a meatier servo.

You might search Google and youtube for monster and giant servo to see mod similar to what you might want.