Fast Guppy’s Speed Shop

Big 3 Upgrade - Universal

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  • $159.99
  • Regular price $199.00
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Our Kit includes everything you need to complete the Big 3 upgrade on most vehicles, you'll get....

-7 Feet of Red Oxygen Free Copper Wire

-10 Feet of Black Oxygen Free Copper Wire

-6 Terminals in the correct size

-Upgraded Marine Epoxy Coated battery terminals with wing nut "spin off" connections for easy removal when servicing your vehicle

One aspect that is often overlooked when installing a high power mobile audio system, off road lighting, winches, on board air etc. is the current capacity of the factory wiring. The wiring put in place by automakers is just sufficient enough to support the current demands of the factory accessories and is rarely able to support much more than that. A fairly simple and inexpensive way to address this is to replace or augment the factory wiring with new, larger gauge wire. This will help greatly to support the extra current draw that a mobile audio system will demand. The “Big 3” name is because we will be upgrading three key wires in the vehicle. Here are the wires you need to upgrade:

  1. Ground wire from battery to frame:
    Use at least a 4 AWG wire and place it directly under the factory ground strap that runs from the negative battery post to the frame of the vehicle. Grind away any extra paint on the frame to bare metal to allow the new, larger ring terminal to make full contact with the frame.

  2. Ground wire from engine to frame:
    This will be almost the same as the “battery-to-frame” upgrade. Use at least a 4 AWG wire and place it directly under the ground strap that runs from the engine block to the frame. Grind away any extra paint on the frame down to bare metal to allow the new, larger ring terminal to make full contact with the frame. In some vehicles there may be a ground strap that runs from the alternator casing to the frame. It would be a good idea to upgrade this also if your vehicle has this.

  3. Power wire from alternator to battery: Use at least a 4 AWG wire and place it under the factory ring terminal on the power stud that is on the side of the factory alternator. Run this wire to the positive battery post and be cautious not to route it where it will contact hot engine components or moving parts such as auxiliary belts. Fusing this wire near the alternator is a good idea as well for added protection in case it gets damaged. This will blow the fuse and still allow the factory system to continue to operate.

The “Big 3” upgrade can not only improve the performance of added accessories, it can also enhance the performance of the entire electrical system for your vehicle (which can lead to improved fuel economy or additional horsepower). In other words, upgrading the “Big 3” is almost always a good idea.

A quick note about wires:

There are many companies offering wire that is a combination of copper and aluminum. Aluminum is not as conductive as copper. Aluminum is also less expensive than copper, so when comparing pricing and wire size it can be a bit misleading. You should only consider using true copper wiring like the kind found in our kit.