[quote author=myork link=topic=71960.msg1269216#msg1269216 date=1173975221]
Ok here is exactly what a BCC or condensor actually does, rubyred3 is on the right track for the most part.
The condensor is actually a voltage stabilizer that is comprised of a number of capacitors matched to a 12-14.4 volt charging system. The effect of a capacitor in parallel with a voltage source is that is smooths out dips and spikes in the votlage. This is exactly how recitifers and AC/DC converters work. So connecting this stabilizer in parallel with your battery helps to keep the voltage stable while the engine is running. It doesnt add any electrical power, it simply stores up some to keep the voltage stable during dips (by releasing the stored energy, but only to a point - this is absolutely NO cure for exceeding the output of the alternator), and by being in a parallel circuit with your battery, helps to keep the voltage down during any spikes.
The condensor itself does nothing to your ground, the additional grounds included with the stabilizer, which are consequently added to the negative terminal of your battery, are what helps the grounding of the vehicle. The effect that each part of the kit has on your charging system are mutually exclusive.
As to their benefits, I have a BCC installed along with a beefed up grounding system, and did not notice or feel any added power (neither of these will add horsepower, unless your original charging system was not properly working beforehand). What I absolutely did notice was that the car does run smoother, and any off idle stumble associated with the ETB was noticeably decreased (it was all but eliminated in my case). My personal opinion is that grounding the throttle body accomplished much of this because the intake manifolds on our cars are plastic which isolates the TB from a real solid ground, other than the small ground wire in the TB harness.
Take it or leave it, but you cannot argue with pure electronic theory, a capacitor in parallel with a voltage source will control the amount of voltage across it, period.
Err, well, I'll argue with it a little. A capacitor in parallel with a voltage source will not control the voltage across the source, in fact it's the other way around. The voltage source controls the voltage across the capacitor. Since the alternator and the battery respond slowly to sudden current demands the capacitor will supply "extra current" that comes fromed the stored charge in the capacitor thereby preventing the voltage from dipping as much as it would have without the capacitor. Of course this doesn't last forever, so if you have a load that is constantly requiring large fast current surges the cars charging system will not be able to keep the capacitor sufficiently charged.