Can I replace the battery with something like 12V or more and the small motors with powerful motors for more speed ?

I have an RC Car that needs 6 AAA 1.5v Batteries in it's batterypack.It has some chip and then switch and two power cords to two Motors-one for turning left-right and another for Going forward and back.will the circuit burn out?

jeff-o6 years ago
It's possible. You'll need to check the maximum operating voltages of all the components inside. If they can all handle 12V, then it should work. But if anything can't, then it may not be so easy. If it's something like a capacitor that needs to be changed to a higher voltage model, no problem. Even a transistor swap would be easy enough. But if any ICs cannot handle 12V then you might be out of luck.

Note that if any components more complex than a capacitor need to be changed, this project may end up being more expensive than just buying a new R/C car. But that's not the point, right? ;)
mayur.phadte (author) 6 years ago
I mean even when it has turned to the max it keeps the turning motor on
mayur.phadte (author) 6 years ago
Did u mean to ask whether the turning motor was a servo?
No it isnt
its a DC Motor!!!
when it isnt turning but I am pulling the trigger on the rc still it applies some force but the tire doesnt turn
A common receiver (chip) in RC cars that use a motor for the left/right function is the RX-2 (may have a A or B at the end). Check to see if this is true in your case. The max voltage on this chip is 5V. Your power supply is 6 AAA batteries or 9V. So, if your chip is a RX-2 then it is having the voltage supplied to it limited in some way to 5V. If they are doing this by taking a tap at the 3rd battery (4.5V) then you would have to create a similar tap or add a voltage regulator circuit to protect your receiver chip.

The H bridges (groups of 4 transistors driven by the receiver chip) for each motor most likely have enough BVceo to handle the 3 volt increase, but might have problems with the extra current. Inspect the transistors for a number that you can search the web with for a datasheet.

The motors would definitely spin faster due to the over-voltage. There are some downsides. Motor life will be decreased and the motors will become much hotter. The hotter motors could actually melt internal insulation or the commutator or the motor bell caps (end part of the motor). 
If you are only using the RC car for a short period at each outing, your motors might be able to take the abuse. 

No one can say for sure without actually going over your car's circuit and build. These type of cars are often built on the hairy edge due to cost constraints. 

Another idea that can increase speed, especially on the larger RC cars is to reduce weight. See if there is anyway to improve the weight to power ratio without killing the "look" of your car.