To be sure there won't be any interference, you'll need to use a BEC to power your ignition. In that setup, you will make a Y connection from the battery, one of which will plug in to your receiver switch, the other to the ignition switch. The ignition switch will then go to the BEC, then to the kill switch and then the ignition. There are two helpful things the BEC does for you: it provides steady voltage to the ignition to improve engine reliability, and it filters out any RF interference that is created by the ignition. Without it, any RF noise that is there will go straight to your receiver since there won't be any filtering between the receiver and the ignition circuit.