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12SI Motor Swap High Output Alternator - One Wire Turn On by JS Alternators

12SI Motor Swap High Output Alternator - One Wire Turn On by JS Alternators

SKU: 8302-320-467

Sale price  $449.00 USD Regular price  $569.00 USD
Shipping calculated at checkout.

Amperage
Pulley

Hairpin units are commonly called 6 phase. They produce more output at idle and are more efficient than a conventional alternator. JS Alternators hairpin units feature premium bearings to withstand high engine rpm and utilize dual plate rectifier with 12 heavy duty diodes for improved cooling. Hairpin Units are a more reliable alternator to withstand high heat, high demand for car audio, marine, and racing applications.

This unit is a direct replacement for standard Delco 10DN, 10SI, and 12SI alternators, making it easy to install on most 1963-1985 GM vehicles. To activate the alternator, you only need to connect a single wire from the provided pigtail to any ignition switched 12V+ source. This allows the alternator to turn on and off with the ignition switch. These units come with a smaller pulley which requires installing a half inch to an inch shorter belt. Make sure to select the pulley design needed for your vehicle in the drop down menu.

All Motor Swap Applications will come with a 45 mm. pulley and will require installing a 1/2 inch - 1 inch shorter belt.

FITMENT GUIDE:

Make Model Engine Year(s)
BUICK All Early Models Most Engines 63-79
BUICK Gran Sport All Engines 65-67
BUICK Riviera All Engines 63-70
BUICK Skylark All Engines 63-79
BUICK Wildcat All Engines 63-70
CADILLAC All Early Models All Engines 63-85
CHEVROLET All Early Models Most Engines 63-85
CHEVROLET C10 Pickup All Engines 63-78
CHEVROLET Camaro All Engines 67-80
CHEVROLET Caprice All Engines 66-77
CHEVROLET Chevelle All Engines 64-73
CHEVROLET Chevy II All Engines 63-68
CHEVROLET Corvette All Engines 63-79
CHEVROLET El Camino All Engines 64-77
CHEVROLET Impala All Engines 63-77
CHEVROLET Malibu All Engines 64-77
CHEVROLET Monte Carlo All Engines 70-77
GMC All Early Models All Engines 63-85
GMC C15 Pickup All Engines 67-78
OLDSMOBILE All Early Models V-8 63-85
OLDSMOBILE 442 All Engines 65-71
OLDSMOBILE Cutlass All Engines 63-76
OLDSMOBILE F85 All Engines 63-72
PONTIAC Early models V-8 63-85
PONTIAC Firebird All Engines 67-70
PONTIAC GTO All Engines 64-71
PONTIAC Tempest All Engines 63-70
PONTIAC Ventura All Engines 71-77

JS Alternators frequently asked questions

How long will it take before my order ships?

Orders ship in approximately 5-15 business days, sometimes sooner. Alternators that require a custom bracket can take 10-25 business days.If for some reason parts are on back order, we will notify you, but this is not common. If payments are being made on an order, your order will start processing when the order is placed.

Is there a warranty for the alternators?

We offer lifetime warranty on alternator labor and a one year warranty on parts. All orders are heavily wrapped for shipping with several layers of big bubble wrap and two layers of boxes along with a Fragile sticker on the box. If you have to ship your alternator back, please be sure you wrap it the same way to prevent further damage.

I'm close to my 1-year warranty, and a part broke. I can't send it in for a few days. Will you still honor the warranty?

Yes. Please fill out our return form at https://js-alternators.com/pages/rga-request-returnsIf this is filled out prior to your one-year date, we will honor the warranty for an additional 90 days.

What is a shorter belt and where can I buy one?

Each of our high output alternators come with smaller overdrive pulley. This pulley is made to increase low RPM charging for maximum output. It is custom for the diameter of the overdrive to be less than your factor pulley, depending on the kind of vehicle you own. For this reason, unless otherwise specified, you will need at least a 1/2 inch shorter belt. You can purchase this from any auto parts store. In using the belt and the pulley system, ensure that each part of the pulley system is free of oil or grease, this will help its efficiency.

Why is a regulator plug important?

It is important to make sure that the small regulator plug that is located on the back of the alternator is well plugged in for the correct functionality. Do not forget to plug it in completely, try not to jam the plugs in backwards, and avoid pinching it in order not to create a short. For more information on regulators and wiring see installation instructions.

Why is it important to not change the pulley provided with the alternator?

Our high output alternators come with an overdrive pulley. The pulley is designed to improve low RPM charging so that it yields maximally. Do not change this overdrive pulley out with a larger diameter pulley. When alternator pulley diameter is increased, the output amperage decreases. Changing the pulley will void all warranties

Why is my alternator not "putting out" enough?

As promised to all our customers, our products are fully tested ensuring their outstanding performance before shipping. In our experience through the years, it is in many cases not the alternator itself. You must ensure you consider a few possible concerns in your troubleshooting – please read the instruction manual thoroughly.

Why is my battery light coming on and/or why is my alternator not charging?

The reason could be one of two things: Either the plug is wired incorrectly or the computer is sensing the higher voltage and causing the battery light to come on even though the alternator is charging properly. Please refer to the instruction manual tab on the website for specific instructions that will help you with wiring. For some older vehicles, the factory style regulator is not available with the hairpin style alternator. This is why your high output alternator will come already “upgraded” with the 15 volt regulator. It will have an oval plug which requires splicing into the factory plug. This is a simple ,fast step and these instructions are detailed for you in the instruction manual.

What voltage will my alternator be set to?

We use your vehicles stock voltage unless requested otherwise.

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