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Big-Three Wiring Upgrade
Three cables, lengths by vehicle type, gauge by wattage.
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From the Catalog
Real products with verified specs. Tap one for the full data sheet.
Gear for this build
In stock at our partner shops — real prices, shipped from people who run this stuff.
JS Alternators
JS Alternators High-Output Alternator
250A–400A+ hand-built in the USA. Find the fit for your year/make/model.
From $649JS Alternators
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Sundown Audio
Sundown Full Tilt 50' 1/0 AWG Cable
50 ft of 1/0 AWG power/ground — the gauge most big-three upgrades call for.
$99.99JS Ultimate Sounds
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Sundown Audio
Sundown Full Tilt 50' 4 AWG OFC Cable
True OFC 4 AWG — for runs where CCA voltage drop won’t cut it.
$119.99JS Ultimate Sounds
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American Bass
American Bass 0-Gauge Distribution Block
Splits one 0-gauge run to multiple amps without a voltage penalty.
$7.62JS Ultimate Sounds
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JS Ultimate Sounds and JS Alternators are run by the ShowUp team — buying there supports the site. Prices as listed at the shop.