This just in, I've decided to keep the Bluetooth as an add-on even if I decide not to have it be used as the primary means of detecting an authorized driver.

This way my phone app will allow you to change certain settings for the system, such as crank time, button press/hold time, etc.

Also to be built into the circuit is a delayed trigger output (optional to hook up) for those of you who want your racekar to have auto TCS off.