am or fm with brushless

[What's_nitro?]

I'm not 100% sure if this applies, but I would move the motor and power leads away from each other to avoid any "cross-contamination". If you have a large amp spike through the power leads I would think it can effect the current in the motor leads if they are close enough. The AM radio is definitely your biggest problem, as the others said. I say go straight to a 2.4GHz radio. I have FM and 2.4. My FM still glitches at certain points on my street (which I now avoid) but the 2.4 is solid.