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XS Power BIG3XS
350-amp Big 3 wiring upgrade kit
Our take on the XS Power BIG3XS by Crutchfield's Jon Paulette
The one-step "Big 3" upgrade kit
If your aftermarket audio system is putting a strain on the rest of your car's electronics, you might want to upgrade your factory wiring. Rated to 350 amps, this "Big Three" grounding kit will boost your electrical system's performance.
XS Power's Big3XS kit includes heavy-duty 1/0-gauge oxygen-free copper cables that replace (or augment) your vehicle's battery ground-to-chassis wire, the chassis-to-engine block wire, and the wire connecting the alternator's positive output to the battery's positive terminal.
Another bonus is that the 8.5 mm ring terminals are already crimped to the wires, so you won't have to replace the stock grounds unless you want to improve them or double up. Extra ring connectors are included, so you'll be able to trim the wires to length and replace the terminals if needed.
The 350-amp Big3XS kit includes:
- 1 6-foot XPFLEX 1/0-gauge power cable
- 2 4-foot XPFLEX 1/0-gauge ground cables
- 8 XS Power heat shrink tubes
- 8 1/0-gauge crimp crimp terminals (already crimped on the wires)
- 10 wire clamps
- 10 zip ties
- 10 screws
Positive cable was the perfect length to reach alternator to battery. Negative cse was good length to ground battery to chassis. But the other negative cable could have easily been only a foot long to go from battery to chassis. This is for my 2013 mustang.
What's in the Box:
- One 6-foot XSFLEX 1/0-gauge power cable with ring terminals on both ends (blue)
- Two 4-foot XSFLEX 1/0-gauge ground cables (pearl)
- Two extra 1/0-gauge crimp-on ring terminals
- 2 Heat shrink terminal protection tubes
- 10 wire clamps
- Ten 3" Zip-ties
- Ten 1/2" Self-tapping screws
- Instructions on the box
XS Power BIG3XS Reviews
Average Customer Review(s):
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Contents: The BIG3XS kit contains the following:
- Power Wire: One 6' length of 1/0 gauge multi-strand power wire in a blue jacket (4704 strands/100% oxygen free copper ). Both ends have ring terminals attached; 0.715" wide and 0.330" inner diameter.
- Ground Wires: Two 4' lengths of 1/0 gauge multi-strand ground wires in translucent pearl colored jackets (4704 strands/100% oxygen free copper). Both ends of each wire have ring terminals attached; 0.715" wide and 0.330" inner diameter.
- Installation Accessories:
- Two additional 1/0 AWG crimp-on ring terminals
- Two XS Power heat shrink tubes (used with the extra ring terminals to protect exposed surface)
- Ten wire clamps
- Ten 1/2" Self-tapping screws
- Ten 3" Wire ties
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Why did you buy this?
The cables are recommended by the manufacturer of my subs because they are 100% OFC (oxygen free copper) , I replaced my alternator with a high output amp (300+ amps) and was advised by the company to do a "big 3 upgrade" , this brand is used consistently by my sub manufacturer when they build systems for cars [ ZACKERY Feb 17, 2016 ]
3 questions already asked
No it will not, the main power wire is only 6 foot long, my suburban needed 13 ft I think to make it to the back [ Andrew Nov 04, 2016 ]
Leave the original cables connected. [ Eric Oct 23, 2015 ]
Leave the current wires and use the XS wires as extra. You'll have more current with the more wire you have. Think of it as a bridge, the bigger the bridge the more traffic that can flow threw same thing applies with the wires. The more and/or bigger the wires the more electricity can flow threw it. [ James Oct 21, 2015 ]
The instructions state that either way is OK. But if in doubt as to what else may be wired up, add these in addition, and leave the original wiring connected. [ JONATHAN Oct 20, 2015 ]
I added to the existing wires. [ RICK Oct 20, 2015 ]
How To Install Big Three Upgrade... look for big 3 upgrade on you tube [ Eric Oct 23, 2015 ]
It's fine to hook as described the only difference it that I would fuse the power from the alternator to the battery with the according fuse for your system. [ Rob Bass Jul 30, 2015 ]
I'm not sure I took mine to a shop and got it done. Sorry I can't help you. [ Rob May 29, 2014 ]