i want to increase my speed on my electric rc car, what increases the speed a new battery or motor?

You have to change the motor.
Go to your local Hobby shop and they will help you out.
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It's been a long time since I messed with anything RC, but if my memory is working, maybe you can find different size gears that fit your car. Changing the gear(s) will affect the top speed.
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There are multiple things you can do. Change the pinon gear on the motor to a bigger gear (more teeth), this is your cheapest way to increase your speed. However this will lower your run time (how long the battery will stay charged). Second you can buy a modified motor but again this will decrease your run time. Third getting a new battery would help increase your speed because you will have constant power to your motor. I have also found a better speed control helps make the car run faster. Or if you have the money do any of my suggestions and this will help
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depending on what kind of car it is you could change the motor or gear but a new battery probly wont do anything for you
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