[cdog4w]

I got mine from potentiality who got his from digikey (they have a minimum order of some kind, so he got 5, I picked up 2, he used one and he sold the others). Not sure on the part number, he'd have to fill you in on it.

Radioshack has a terrible selection of caps. Basically you're looking for a few different features in a capacitor for this purpose. You want somewhere in the thousands of uF range, so I've heard of 2000uF, 4700uF is very common, and I haven't seen many go higher at this scale. Smaller size uF will do more to smooth voltage drops and reduce engine noise, higher will actually give you a bit more punch on takeoff. There are whole debates on the optimal capacity since the more capacity, the longer it takes to recharge after dumping it (say on hard acceleration). The other number you need to know is the voltage capacity. It'd be pointless for you to get a 50V cap when all you need is 10V or so, all the extra V capacity does is make the cap larger. Also, don't go by the straight 1.2V rating for this, since many packs peak at higher voltages (my 6 cells peak just under 9V). Finally you can get special purpose capacitors. In this case, potentiality picked up low impedance capacitors, which means low internal resistance and more power to the motor. You'll also see a lot of 4700uF 16V caps which will work fine too.

To solder the cap in, solder it parallel with the batteries to the ESC. So on my spy, I soldered the battery wires on the top, cap wires on bottom of the connection plate.

Finally, since you're about to throw on your mamba, you might not need it. I have no idea how power capacitors interact with brushless systems. I would guess that there is less motor interferance simply due to the design of a brushless motor (which is cool sh**), but maybe thats just because they're hella expensive.

If anyone has anything to add/correct, please do as I am by no means an expert.