do I need a larger alternator? -
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Go Back > General Technical Discussions > Stereos, CB & Ham Radios, GPS, & Electrical. > do I need a larger alternator?

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Unread 02-23-2009, 12:12 PM   #1
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2004 WJ 
Join Date: Apr 2004
Location: Portland/Eugene, OR
Posts: 374
do I need a larger alternator?

I'm currently running a true 750-1000rms single JL 12" W7 subwoofer powered by a JL 1000/1 amp. I'm about to install a 4x100rms alpine pdx amplifier to power a set of infinity kappa components for the front and kappa 6.5" 2 ways for the rear... would it be strongly recommended to upgrade to a larger alternator? I have the 4.0 WJ, whats the output of the stock alternator?

IRO 3", BFG MT KM2 31's, MX-6's
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Unread 02-23-2009, 12:55 PM   #2
Jerry Bransford
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2004 TJ Wrangler 
Join Date: Jan 2003
Location: Escondido, California, California
Posts: 62,979
Your alternator is fine. That setup doesn't draw that much power for normal listening levels. Only if you had it cranked up enough to provide sound for a stadium or competition event would it draw even close to what it can draw when it's putting out all of its power. The peak amperage comes right out of the battery when needed. Your alternator is likely 117 amps.
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