So if I understand you: it's an electromagnetic coil, moving a magnet, which is somehow linked to the suspension? Or I guess you could link it to like a stick which goes down through the chassis and pushes it up. (cheating, but it would sorta work) The other way would be another motor with an eccentric cam. (but that would suck because it would be constant hop) Which in turn gives you the mad hopping motion (atleast twitching) and maybe some three wheel action if you're crazy enough to design it.
Could work, but you've gotta run another channel, or free up one you've got. (booster Bit board swap? ZZ board with no reverse?) You could atleast get the front hopping that way!
If you wanna do full action "hydros", you'd be better off to use something like Epoch racer size or bigger (1/43 scale). Just because they're easier to mod due to being bigger so you've got more room to smuggle extra parts.
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Dude, I just realized how you do it *sorta* easily!!! Dip Switches. You set it up so that in one position you get stock ZZ setup, and if you flip all of them the other way you get full on lowrider. You'll probably need 2 banks of dips. That way you can select what channel goes where!!!
You turn off just the "steering" and turn on the "front hopper coil" you'll have a free channel to use for something else (can you say rear hop coil?), and you can still use the throttle. *Hop it down your 1/64 scale ghetto street and pick up little 1/64 scale hos?* If you're going like a full on show-car Lowrider, you can go ahead and make the back articulate too (H-plate?), and wire it so you can turn "motor" off also and turn on the "side/side" set of coils you can do front/back and side/side! The weight of this thing should keep it low and when you power the coils it'll raise. Not perfect, and no three-wheel; but, it'll probably get ya bouncin'!!!
After you finish that wicked monstrosity, you're probably gonna need like the biggest ZZ body they make (like a Jeep CJ-7, a Ford F-150 with a custom built truck cap, or stationwagon like a Suburban, Escalade or something). Maybe even make like a stretched chassis and do like a hearse. Large body is so you'll be able to relocate stuff inside to make it all work. Then you mount the body like a Mini-Z, front tab and something clamping the sides of the chassis tub. Batteries probably moved above board so you can hide the dips, coils and wiring inside the chassis tub.
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Now, the thing I *DON'T* know about
: how will all those extra magnets affect your radio? You might not even be able to have the car get signal when you've got the magnets in and/or the coils hopping. If it won't work you could probably try to shield it, but I don't know!
If the thing's RC stuff WILL NOT work when the coils are in use, but WILL with the magnets onboard; you could probably get by with like a switch on your Tx that shuts off radio signal output and switches it to a 4-pin plug kinda like the ZZ SE uses for lights, and put a corresponding connector on the car. That way you could run it hardwired from outside the car like they do at the lowrider competitions. Then flip a switch on the Tx, pull a connector, and drive off!
It's 0430, so if I'm way off on something I'm just tired and ignore my babbling. If what I said makes sence to a well rested person, let's talk I think I just might have engineered one.