Why Is The Big 3 Wiring Upgrade Kit Required for All High Output Alternators?

 If you're upgrading your stock alternator to a high output alternator, it is required to upgrade your wiring to a big 3-wiring upgrade kit. A common myth is that you don't need to upgrade your wiring if you aren't running an aftermarket car audio system or other aftermarket products. However, this is not true. Big 3 wiring kits are ALWAYS required when upgrading to a high-output alternator. 

The Big 3 Wiring Upgrade Kit comprises high-quality wiring materials designed to increase power transfer from the battery to other electrical components in a vehicle, including amplifiers, subwoofers, and speakers. A High Output Alternator further increases this power by generating a higher current than traditional alternators typically produce.

This article will examine the benefits of these upgrades when combined with proper installation techniques and knowledge.

The Benefits Of The Big Three Upgrade Kit

The Big Three upgrade kit is a great way to enhance your vehicle's aftermarket system, as it allows more current flow to all of your aftermarket components, thus improving the vehicle’s electrical system.

It involves replacing three main cables with 1/0 100% OFC (Oxygen Free Copper) wires. If you need to purchase a big 3-wiring upgrade kit, you can do so by clicking here. 

Moreover, this wiring kit also helps improve grounding and allows the increased power to safely and adequately flow throughout the vehicle. 

The Big Three Upgrades Explained

The Big Three upgrade involves replacing or augmenting the factory wiring with thicker, higher gauge wires for better current handling capacity.

The three main components in this upgrade are typically referred to as the “Big Three”: an upgraded power cable from the alternator positive post to the positive on the battery, and an upgraded ground wire from the alternator mount bolt to the frame or chassis, an upgraded ground wire from the negative on the battery to the frame or chassis.

Installing a high-output alternator and a Big Three Wiring Upgrade Kit is essential to take full advantage of a powerful vehicle's system and ensure it performs optimally.

JS Alternators' most popular products are the Big 3 Wiring Upgrade Kits, and we offer two different types; both are 100% OFC (Oxygen Free Copper) 1/0 wires.

    1. Universal Big 3 Wiring Upgrade Kits - Universal is the most commonly purchased Big 3 Wiring Kit; however, please check the measurements to ensure they will work for you before purchasing.  
    2. Polaris Slingshot Big 3 Wiring Upgrade Kit - The Polaris Slingshot version comes with a long positive wire than the universal kit, allowing for more customization options. This one is commonly used for the Polaris Slingshot vehicle or vehicles with batteries in the trunk. Please check the measurements for your car before purchasing. 

Installation Guide For The Big Three

The Big Three wiring upgrade kit is a great way to enhance your vehicle and get the most out of your aftermarket system. The tools needed for the installation will vary based on your car, but a socket wrench will usually suffice.

For specific JS Alternators Big 3 Wiring Upgrade Kit installation steps, visit our guide here: Boost Your Electrical System With a Big 3 Wiring Upgrade Kit: A DIY Step-By-Step Installation Guide.


From improved power efficiency to better sound quality, these big 3 wiring upgrade kits provide a range of benefits that will enhance your audio experience and aftermarket accessories. Remember, if you're upgrading to a high output alternator, it is ALWAYS required to upgrade to a big 3 wiring kit too!