The Big 4 Upgrade [Benefits & Diagram]

There are several convincing reasons to do a Big 4 upgrade on your car instead of a Big 3 upgrade. One of them is if you have an older car with bad or deteriorating ground straps. However, that is not the only reason to perform a big 4 upgrade.

There are reasons/benefits of performing this upgrade that I will be discussing in this post, along with what the Big 4 upgrade is, its cost, wire size, and upgrade kit, and how it compares to the Big 3.

The Big 3 Upgrade

If you are familiar with car audio, you should already know about the big 3 upgrades. Long story short, the big 3 upgrade entails replacing three of your car’s main wires with lower gauge (thicker) wires, which provides a smoother path for current to flow, culminating in a more steady flow of power to your electrical gadgets.

• When you have running from the alternators positive terminal to your front battery positive a 0 gauge wire that makes the alternators put more amperage and higher voltage out from the alternator with less resistivity in shorter wires so you get good electricity from your alternator to the plus side of your car’s front battery.
• When you have a bigger minus side so you have a good grounding in your front battery. Also, this helps when you have a good positive side, a good grounding in your front battery if you have an amplifier back in your car that is grounded into the chassis of the car. So, without having upgraded 0 gauge wire from your front battery, your car gets only gets as much amperage out from your front battery as the small grounding wire allows through.
• When you have all the alternators and the battery in your engine bay, you must also upgrade your engine’s ground to the chassis of the car; the engine usually has this kind of bad wiring, which is normal stuff. What car manufacturers ground their engines into the chassis, it is not even copper so the ground is bad in your engine and when your alternator grounds itself through the engine, through a bolt, the engine needs to be better grounded to get all the power from the alternator into your front battery

The Big 4 Upgrade – Full Explenation

Now, all of what I said above is good, especially the zero gauge wiring all around the car but we are missing one very important step, which completes the Big 4 upgrade. We need to think about how alternators work to find out what the big four are.

Now, when the alternator is working, it has the stator side; this goes around inside of the stator and the stator produces a sine wave so you have the first set of the sine wave, second and third. When you connect them through the diode rectifier, it pops them up and produces DC electricity.

Now the engine has a better grounding but if you run a few wires to the chassis of your alternator, you get better performance from your alternator into your front battery and that is the big 4; the fourth one is grounding your alternator properly.

Now, this is hard to ground; maybe you have a long enough bolt from where you connect this into the alternator bracket. Maybe, you have a long enough bolt so you can put an extra cable in it and ground it strictly straight into your front battery.

Or the best way – when the diode rectifier side connects to the backside of your alternator, you can see there are many grounding points in this alternator and if you can ground this chassis better into your front battery, the output of the alternator is much better.

Now, I think using a zero gauge wire here would be a bit foolish because the alternator is located in a difficult spot. You are dealing with very small bolts, so maybe you can use two or three or four smaller wires where one or two connect into the front battery and one or two connect into the chassis of the car, hence producing more amperage out because it’s grounded better.

The Benefits

The Big 4 upgrade offers several benefits. I noticed that since I performed the upgrade on my car when pulling the window down, the gauge barely moves. And this doesn’t just apply to newer vehicles; it works on older cars as well.

The Big 4 upgrade made a huge difference not only in the life of my battery but just the drain overall on my charging system.

I noticed that my gauge wasn’t dipping as low. Making these upgrades was a huge difference; a big thing I noticed was that my lights weren’t as dim at night and especially if I had like my blower on or anything like that such as running my heat or AC.

I also noticed that my windows seemed to run a little bit faster; just everything overall seems to work a little bit better so like I said huge upgrade definitely takes the strain off the alternator battery and the overall charging system. You know if everything’s getting the power it needs, everything’s going to function a little bit better.

Big 4 Diagram

• First: upgrade zero gates from your alternator into your front battery into the positive side
• Second: upgrade your front battery negative terminal to like chassis of the car with the zero gauge wire
• Third: upgrade your engine grounding to the chassis of the car with the zero gauge wire
• Fourth: upgrade your alternators grounding with multiple cables in the chassis of your car to produce as much electricity and amperage out as possible into this car battery

The Cost

The cost of the Big 4 upgrade varies greatly depending on the lengths needed in each vehicle.

The most precise way of calculating the cost of this upgrade is to assess the path of all four wires, calculate the cost of 0 gauge OFC wire per foot, and make inquiries about the labor fee for your specific application.

The Wire Size

Copper wire (OFC) is strongly advised for the highest conductivity when conducting a Big 4 update. Aluminum is a less expensive and more widely used wire, but it is less conductive.
Copper/aluminum wire (CCA) and welding cables are also available. If you go with this option, the 2/0 AWG OFC audio cable is the same as the 1/0 AWG OFC audio wire.

The Upgrade Kit

Each of the Big 4 Upgrade kits includes lock washers, zinc-plated internal/external star washers, flat washers, and Grade 5 bolts. Since terminations are equally important, the kit includes lugs that can be tied using a tightening press to meet industry-standard pull tests.

Big 4 Vs Big 3

By updating the three primary wires, the Big 3 Upgrade ensures that you get the best performance out of your alternator. They all constitute the charging circuit and must be updated if you use aftermarket electronic devices that put additional strain on the charging system.

On other hand, the Big 4 upgrade allows you to get better performance from the alternator into your front battery. When you think about the factory grounds under the hood, especially the body grounds that tend to be very small, and when you think about the number of electronics that are run off those body grounds, a Big4 upgrade can make a huge difference, more than a big 3 upgrade.