The Big 3 Upgrade [How To & What]

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What is the Big 3 upgrade?

The Big 3 Upgrade entails replacing three primary wires in your car’s electrical system with lower gauge (thicker) cables, leading to a cleaner channel for electricity to travel and a more steady flow of power to your electronic equipment.

The Big 3 Upgrade is a fairly affordable and straightforward upgrade that boosts current carrying capacity in three crucial spots in your electrical system (thus the name) by adding larger gauge wire to the original wire or replacing the factory wire entirely.

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In this post, we will cover all you need to know about the Big 3 Upgrade, including what it is, the benefits of performing the upgrade, its cost, and more. There is also a Big 4 upgrade.

What are the Big 3 wires?

The term “Big 3” comes from the fact that we will be upgrading three critical wires in the car. The following are the wires that must be upgraded:

Charging Wire from the Alternator to the Battery Positive Terminal

Utilize at least a 4 AWG wire and connect it to the factory ring connection on the power stud on the OEM alternator’s side. Connect this wire to the positive battery post, being careful not to let it come into contact with any hot engine parts or mechanical components like auxiliary belts.

It’s also a good idea to fuse this wire near the alternator for further protection in case it gets broken. The fuse will be blown, but the factory system will continue to function.

The Chassis Ground Wire to the Negative Battery Terminal

Choose where your ground wire will connect to the chassis. You can bore a hole in the frame and attach the wire with a stainless steel fastener if a solid, bare metal region is not easily accessible or desirable. You may also require a wire wheel to remove the paint off the metal, leaving it bare.

Attach your new ground wiring to the negative pole of the battery and fasten it once you’ve made your decision. Connect the cable to your new chassis grounded point and secure it.

Engine Ground to Chassis Connection

The third critical place for the Big 3 Upgrade is less evident than the other two, but it is no less crucial. When the engine is operating, the alternator is the principal source of power for your car’s electrical system, and no DC circuit is effective without a return connection to the ground at the source.

With the last upgrade, we took care of the return path to earth at the battery, but where is the returning path to grounding for the alternator?

The alternator’s grounding “terminal” is the case itself, and a manufacturer wire that links the engine to the frame links this to the remainder of the car’s ground system.

Your big three updates will be finished once all three of your new wiring have been installed according to the instructions. This new wiring will enhance the management of current flow to your stereo parts by your electrical system. As a result, you should be able to avoid or reduce the symptoms of a strained electrical system.

What Are the Big 3 Upgrade Benefits?

Better resting voltage (13.8-14.6V), less voltage loss (less light dim), and an increase in performance of the car’s electrical parts are all expected benefits of this modification.

It eliminates the need for any extra external amp power capacitors, which are usually merely a Band-Aid solution to a long-term problem.

We effectively perform a surgical operation on the factory electrical system with the Big 3 Upgrade, ensuring that earlier difficulties are less likely to arise in the future.

Big 3 Upgrade Diagram

The greater the diameter of the wire, the better. Since you won’t need to modify your wiring afterward, 1/0 AWG ground and power wiring is a common choice. Any wire larger than the factory wiring, on the other hand, will aid boost current flow.

What Is the Big 3 Upgrade Cost?

The cost of the Big 3 Upgrade varies widely, according to the different lengths required in each vehicle. The most accurate way to estimate the cost of this upgrade is to measure the path of all three wires, determine the cost of 0 gauge OFC wire per foot, and inquire about the labor fee for your unique application.

What Is the Recommended Big 3 Upgrade Wire Size?

When performing a large 3 upgrade, copper wire (OFC) is recommended for maximum conductivity. Aluminum is a less expensive and widely used wire, although it is not as conductive.

You can also get copper/aluminum wire (CCA) or welding cables. If you choose this alternative, 2/0 AWG OFC audio cable is equivalent to 1/0 AWG OFC audio wire.

Why Is a Big 3 Upgrade Kit Needed and What Is Included In It?

Between your audio system, battery, and the alternator, the Big 3 upgrade kits provide an incredibly low resistance feedback path. The kit will substantially improve the return path using the vehicle chassis if you possess a unit-body vehicle. If you have a body-on-frame car, the kit adds a new return path–the frame–that can handle very high current.

In either case, the kits increase the charging system’s feedback path, which enhances the return path to all of your factory electronics and electrical components, such as current-hungry fuel pumps and electric fans. It’s not uncommon to witness a boost in the performance of stock components after using one of these kits.

This is the upgrade kit we recommend.

NVX True Spec 1/0 Gauge 100%...

The connections between the wires and the chassis/frame are critical to the upgrade’s success, particularly as time passes. To correctly secure each cable, each of the Big 3 Upgrade kits comprises zinc plated internal/external star washers, Grade 5 bolts, flat washers, and lock washers. Since the terminations are equally vital, the kit features lugs that can be attached using a tightening press to satisfy industry-standard pull tests.

Tinned lugs are resistant to corrosion and oxidation, which attack normal copper lugs very instantly. Furthermore, compared to normal thin-wall copper lugs, these lugs have a larger contact area with the mounting surface, resulting in lower resistance linkages.

Lastly, each lug is protected with super-thick, adhesive-lined heat shrink to prevent the elements from penetrating and damaging the cable-to-lug connection.

When you bolt the provided ground cables to your car’s chassis and frame according to the included guidelines, you’re creating a long-lasting connection. With the Big 3 Upgrade kits, you only have to do it once correctly, and then you can forget about it.

Can A Big 3 Upgrade Stock Alternator?

One final question that you may have in mind about the Big 3 upgrade is if it can upgrade the stock alternator.

You won’t get exceptional performance from your sound system if your alternator can’t transfer sufficient power down the line, regardless of how thick the wires are. It’s necessary to upgrade your alternator if this is the case.

The Big 3 Upgrade will guarantee that you achieve the optimum performance from your alternator by upgrading the three primary wires. Together, they all form the charging circuit and will need to be upgraded if you use aftermarket electronic gadgets that place extra strain on the charging system.

If your audio system requires more power than your factory alternator can provide, switching to a higher output alternator will be beneficial. Although replacing your standard alternator with a “HO alt” may appear to be an expensive option, if you’ve spent money on a sound system that consumes this much power, you shouldn’t think twice about addressing this supply and demand issue by increasing power supply.

A bit longer explenation?

A big 3 upgrade will let more current flow to all of your stereo parts, which will improve your electrical system by guaranteeing more stable voltage. This update requires upgrading your electrical system’s three main connections with 4 gauge or 1/0 wires.

When you start to add aftermarket hardware, the Big 3 upgrade helps you to minimize the impact of the factory wiring being substandard. This update also prepares you for the transition to a high-performance alternator.

To explain it briefly, the Big 3 Upgrade is a three-point upgrade to your car’s factory wiring that allows electricity to flow more freely and lets you use your factory alternator to its maximum potential.

You might be thinking: “why do we bother so much about the alternator when the battery is the power resource for all the electronics?”

That’s only half the truth. When the engine is turned off, the battery is the major source of electricity for powering up and activating the electronics. When the engine is operating, however, the alternator produces a higher voltage than the battery. When the engine is working, it can charge the battery and become the principal source of power for all of the car’s electronics.

Last update on 2024-07-24 / Affiliate links / *Image Disclaimer: We use images/data from Amazon Product Advertising API solely on products that link to Amazon. On products with the "Price at Crutchfield" button, we use images/data from as per the partnership deal.

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