How To: Install the Big 3 Upgrade

Hello and welcome! Today, we are going over what the big 3 upgrade is and why it is an important part of your car stereo! 


What is a big 3 upgrade?

Most car manufacturers use just big enough cable to cover the needs of the factory vehicle. So, once you add some amplifiers to it and start trying to pull power, the vehicle was not ready nor set up for that! So, adding a big 3 upgrade will allow you to pull some more current from your alternator and help keep your voltage up and those dimming lights away! You are upgrading the charging power cable, and adding 2 solid ground connections to the frame, as well as to the motor/alternator. This allows you to get full potential out of the factory alternator, or even an aftermarket alternator should you go that route! 

Do I need a big 3 upgrade?

Probably the most common question we get is, at what point do I need to get a big 3 installed? Well, for us personally, we do them on all of our vehicles whether it has a big stereo or is completely factory! It never hurts anything to help your vehicles electrical flow batter and the big 3 upgrade is just that! Although, if you have over 1,000 watts of amplifier power you are probably due for a big 3 upgrade! 


How do I wire my big 3 kit?

Lets start with laying out the big 3 kit and making sure we have everything we need to get started! Your kit should have came with 1 colored power cable and 2 black cables. There should be a total of 6 ring terminals as well as color matched heat shrink to seal the connections! Be sure you have cable cutters, wire strippers, and zip ties as well! If you have not yet ordered your big 3 kit, check them out here!

Now let's get started!

First, we will start with our power cable. Grab your power cable (whatever color, most use blue or red for this, but any color will do as long as you know that color is power!) and route out how you will run the cable from your alternator positive post to the positive post on your battery. (Remember to keep the cable away from any heat as well as make sure that you have areas to secure the wire in place with a zip tie along the route) Measure twice and cut once! Once the cable is cut, add a ring terminal and your favorite heat shrink to each end of the power cable, connect it first to your alternator and then to your battery! (Optional: If you are wanting to add a fuse to the power cable, now is the time! Be sure to find a safe and secure spot, as well as accessible should you need to replace the fuse, then mount and wire the fuse into place!) 

Now, we will move onto the two ground cables! Most of the time people use black for their grounds, but just as before grab whatever cable color you know to be ground and let's get them routed!

With the first ground, we are going to go from the battery negative post to the vehicles frame. You will want to try and find a spot that you can use a factory bolt, or even drill a hole and us a bolt to secure the wire with a ring terminal in place. You will also want to clean the surface of the frame where your ring terminal will touch so that you can ensure a solid connection. Again, measure twice and cut once! Once the cable is cut, add a ring terminal and your favorite heat shrink to each end of the ground cable and connect it to the battery negative post and then to the frame. 

With the second ground, we are going to do all of the same steps as we did above, but this time we are going to be going from the battery negative post to a ground spot on the alternator directly or a motor ground of some sort. Some alternators have a bolt on the case that allows you to connect straight to the case, others have gotten good results using one of the bolts that holds the alternator in place. This will be tricky and may take some time to get a good spot figured out and cable routed to it. 

*** Be sure to run your power wiring that is going to your amplifier FROM THE BATTERY POSITIVE (+) POST! Do not run your power wire from your alternator directly to your amp!***

All Done!

You have now installed your big 3 upgrade! Start your vehicle and confirm that your voltage is the same as before at idle (if not better already!) and then try putting a load on your electrical by playing a song that has heavy bass tones. You should notice that your lights flicker less, or even not at all now! 


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