We were lucky to be introduced to engineering student and drone designer Kai Lin, who showed us how to use open source software to make our cars radio controlled. Below are links to the electronics.
Note from Kai: “Modules are a bit tricky because there are different sizes for different remotes. The most typical is micro JR and nano, both of which I will link here. You need the 2.4ghz variant. You can find them at most stores, just make sure they are “ELRS 2.4ghz” and fit your radio. As the protocol is open source, you’re not constrained to a single brand, which is super nice.”
Controller: https://www.radiomasterrc.com/products/zorro-radio-controller
Here are the links for the motor controller and throttle (servo tester):
Controller: https://www.amazon.com/dp/B071GRSFBD?psc=1&ref=ppx_yo2ov_dt_b_product_details
Throttle:https://www.amazon.com/gp/product/B07TQSKLBK/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Battery: The ones we used were given to me so let me know if you know of a good .5A 2s or 3s LiPo battery.
Arduino RC tutorial (this is what we did during our Build Hack Make follow-up workshop): https://howtomechatronics.com/tutorials/arduino/arduino-wireless-communication-nrf24l01-tutorial/