Car Stereos: H/O alternator, watt stereo system, alternator pulley

Question
QUESTION:  I had a 200 amp h/o alt installed along with the big three upgrade with 1/0 wire.  I only have about a 1000 watt stereo system in my 2004 chevy impala and when I turn the bass up during idle at night my lights still dim.  I thought a H/O alt would stop that.  Do you know what's wrong?


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Answer   The alternator and wiring upgrade is definitely a good idea to keep from ruining car components such as alternator, wiring, battery, etc., but the light dimming will still happen on hard hits, because they require so much more power than when not hitting hard.  The cure for the light dimming and to make the bass hit even harder is a capacitor.  Usually in a system under 1000 watts, 1 farad capacity is enough to do the job, but you can buy any size larger, and it will work the same.  The capacitor stores up extra power, so when the bass hits hard, the power is available and it is not robbing from other components.  It just gets installed just before the amp on the main power line.  That will fix your problem.  Good Luck, Scott

 
Scott, I forgot to mention I have a 2 farad tsunami cap installed also and the light still dim

roger


Answer
There is one more possibility.  If you have more than a 2000 watt rms total system, the capacitor could be not large enough, but I am guessing not.  So, the other possibility is an alternator underdrive pulley.  Do the lights dim while you are driving with the engine rpms up over 1000?  I am guessing that they only dim while idling.  Sometimes the alternators don't spin quite fast enough at idle to put out full power.  You can buy an alternator pulley that is slightly smaller than the original, and that will spin it just enough faster to charge full power even at idle.  You can pull the alternator and take it to an alternator repair shop, and they should be able to install the new pulley for you.  It is really odd that your capacitor cannot keep up with your system, unless you play it alot at idle.  After that, you are going to have to look into splitting up your power supplies, which involves an extra battery, electronic charging switches, and more wiring.  Let me know if this does the trick.  -Scott