FCC legal stuff says you can only run 27 and 49 for landbased RC craft. Blah blah blah, I didn't tell you anything, don't to anything I say, blah blah blah.
Ok, so probably the best way to be able to run 3 cars at once is to get 3 of the ZZ-SE models, you can run 6 of them at once, and they're all on the 27mhz band, so you can also run one of the base models on 49mhz.
You could always get a "bullet clone", they're knockoff Bit Char-G / Microsizers, and most of them are on the illegal freqs. I think I've gotten some on like 27, 35, 40, 45 mhz... Component or Board swap pretty easy if you're handy with an iron.
These cars aren't quite good enough to have a crystal in the RX, but that's ok the weight would slow them down anyway. They use a tuning coil, it's a ferrous plug that you screw in/out of a plastic thing supporting a coil. That changes the ressonant freq of the RX; it works decently, but it's not selective enough to run like a Tx on 27mhz ch.1 along side another TX on 27mhz ch.7 because this type RX is not very selective. The tuning coil is generally white, and the top is filled with a soft wax.
Let me know if you like any of those options, and I'll try go into more detail on it. I'm tired of typing
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Alright, now let's see some pics of your P-body.
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