When installing a car audio system of 1200 watts or more, you need to do a big 3 upgrade.
This may seem daunting, but it is a simple process.
What is the big three upgrade?
Big 3 upgrade is the process of upgrading your car’s stock wiring to provide the best flow possible for your new car audio system.
The wiring you upgrade when you do a big 3 upgrade serves not only the car audio system but the electrical needs of the whole car. The thicker wiring will allow increased amperage flow, which will benefit your big wattage amplifier or sound system.
Instead, the big 3 helps to balance your electrical system and boost the flow of current. It does this by taking the strain off the factory wires and providing more amperage flow.
During the process there are three wires you’ll be upgrading.
These are the:
- Charging Wire, which runs from the positive side of the battery to the alternator.
- Battery Ground, which runs from the negative side of the battery to the chassis of the car.
- Engine Ground, which runs from the engine to the chassis of the car.
You might be asking yourself, ‘do I really need a wiring upgrade?’
The wonderful thing about a big three upgrade is that it has no downsides. Even if your car’s stock wiring can accommodate your audio system, upgrading your wiring can:
- Better the performance of the whole electrical system
- Help the starter perform better when starting the car
Meaning, it’s a win-win situation, whichever way you look at it.
How to do the big 3 upgrade
You’ll need some tools for this job. Each engine bay is different, so the tools you use may differ, but you should definitely have some:
- Zip ties to tie down the wiring every couple of inches
- Hammer crimps or blowtorch with a solder
- Utility blade
- Wire cutters, big enough to cut the wire you are using
- Stainless steel bolts and nuts
The bigger the wire, the better. 1/0 AWG ground and power wiring is a popular choice because you won’t need to upgrade your wiring after this. But, any wire bigger than the factory wiring will help improve current flow.
|Voltage||Amps||< 5 Ft||5-10 Ft|
|12 Volt||0-60||8 AWG||4 AWG|
|12 Volt||60-100||6 AWG||4 AWG|
|12 Volt||100-150||4 AWG||2 AWG|
|12 Volt||150-190||4 AWG||1 AWG|
|12 Volt||190-250||2 AWG||0 AWG|
|12 Volt||250-300||0 AWG||2/0 AWG|
For optimal conductivity, you should use copper wire (OFC) when doing a big 3 upgrade. Aluminum is cheaper and is a popular choice of wire to use, but it is not as conductive.
Alternatively, you can buy copper/aluminum wire (CCA) or welding cable. If you go with this option, get 2/0 AWG it’s the same as 1/0 AWG OFC audio wire.
If you’re unsure about how to source your wire, here are a few options:
- Buy individual lengths of wire from your car audio store
- Buy a big 3 kit, which comes with the specific wires and connectors.
If you can wiggle your connector when it is crimped, then it’s not tight enough.
Before you start your upgrade, disconnect the negative battery terminal. This will ensure that you don’t short out anything during the upgrade.
Then, make sure you know where the alternator, engine, and battery are. Every car is different, and these may be in different places than what you’re used to.
These can be a bit challenging to find, depending on the layout of your car. But it is best to find them first so that you know what you are dealing with and can get all the tools you’ll need.
Next, find where all the existing wires connect and run. This will help you decide how you’re going to run your new wires and where you’re going to connect them.
When you install the charging wire, make sure it is wrapped of split loom or tesa tape. This will protect it against short circuits and heat.
Take your wire and connect it to the positive battery post and run it to the factory ring terminal on the side of the alternator. Be careful not to run it along a route where it may be in contact with moving or hot parts of the engine.
A good idea is to fuse the wire close to the battery, to prevent it from getting damaged. If the wire does get damaged, it will blow the fuse and the factory wires will continue to work.
You may be thinking, ‘why are we bothering with the alternator? Doesn’t all the power come from the battery?’
That is partly true.
The battery is responsible for starting everything up when you start the engine. But as soon as you start the engine, the alternator charges the battery and provides power to all the car’s electronics when the car is running.
But if you have an 80amp alternator, you’re gonna get 80amps. No matter the size of your wire.
Next up, we need to connect a ground wire to the battery and chaise of the car. Try and keep your ground wires as short as possible.
Place your wire under the ground strap of the already existing ground wire on the battery.
The best option is to connect the ground wire directly to the body of the car on top of the already existing ground wire.
If you see an easier route to ground your wire, go ahead and use it. Remember to ground it directly to the body of the car, doing this will ensure a long-term connection.
If you choose a new spot, make a small hole, remove any paint, and clean it. The upgraded, larger wire must have direct contact with the chassis.
The last wire is the engine ground. This is similar to the battery ground but runs from the engine block’s ground strap to the chassis.
Connect your wire to the ground strap and then ground it on the chassis. Like with the battery ground, you can either ground it in the same place as the existing ground wire or choose your own.
If you choose a new grounding area, make sure to remove any paint so that the upgraded, larger wire has complete contact with the chassis.
If your car has a ground wire running between the alternator and chaise, go ahead and upgrade it while you are at it.
During the upgrade, you may need to make some minor adjustments like:
- Drilling a slightly bigger hole
- Shaving down a screw to fit the bigger wire
- Shortening your wire
- Crimping your connectors
Be sure to set aside enough time so that you are not in a rush or under pressure and you can do a good job. This is a really easy procedure that you can do yourself, just make sure you understand what needs to be done and what you’ll need before you start.