Our radios are certified, so are the receivers.
They are howevernot certified to resist high RFI levels from other interference sources.
Ignitions also are not certified to high levels, that is why NO ignition manufacturer in his right frame of mind sells his ignitions without the statement that they are for model airplane use only, and that the user should keep a certain distance between the device and radio gear.
Now, I wonder why they do that?
I also wonder why some *heads find it safe to ignore that warning.
I cannot stop wondering if I see people actually promoting the ignoring of the warning.