my cars voltage

[controlfreek654]

I've noticed in the recent past that when i have my capacitor hooked up that all of the guages in my car read @ 14.2 volts and as i thump for a while the volts slwly slpit to about 13. (i have a digital auto meter guage and a 1 farad monster cap w/ digital read-out. im only running 2 amps (lanzar)? Is this normal - im not to informed on caps. Thanks

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[CWT 10+ year member]

The gauge your looking at is actually reading the car's charging system voltage. And while the engine is idling, it is pretty normal for the system voltage to drop down to about 13.3-13.8 volts. Normally this happens as soon as the engine returns to idle; what your reading is probably the cap slowly leveling down to the same level as what the alternator is puting out. Most alternators I've seen won't crank up to 14.2 volts; and only if the demand is there; until the engine is doing at least 900 rpm; which is just above idle in most cases. If your getting 13 or more volts at idle, sounds like it's running just fine too me. Drive around a bit and the cap will charge back up to max capacity.

About the cap: A capacitor is a temporary energy storage device. Like a shock absorber, its primary purpose is to absorb the momentary shock loads (Every time your subs go "thump", for example) that an amplifier can put on a car's charging system. It's basically protection; the cap takes the "beating" from the amps in order to protect the battery and alternator.

Thump in peace. CWT