250-amp Big 3 wiring upgrade kit

  • XS Power BIG3XP



Our take on the XS Power BIG3XP

by Jon Paulette
XS Power

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 250 amps, this "Big Three" grounding kit will boost your electrical system's performance.

XS Power's Big3XP kit includes heavy-duty 1/0-gauge copper-clad aluminum 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 Package

This Big3XP 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 terminals (already crimped on the wires)
  • 10 wire clamps
  • 10 zip ties
  • 10 screws

Warranty: 1 year

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What's in the box?

Download owner's manual

  • One 6-foot XPFLEX 1/0-gauge power cable with ring terminals on both ends (blue)
  • Two 4-foot XPFLEX 1/0-gauge ground cables (black)
  • 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

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At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team — they open the box, verify contents, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.


Contents: The BIG3XP kit contains the following:

  • Power Wire: One 6' length of 1/0 gauge multi-strand power wire in a blue jacket (5250 strands/10% oxygen free). 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 black jackets (5250 strands/10% oxygen free). 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 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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XS Power BIG3XP Reviews

Average Customer Review:

6 people say:

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4 out of 5

Big 3 Wiring Kit

Written By C, Foristell MO on Thursday, July 17, 2014
Crutchfield Customer Review (What's this?)
I have a 1,200 watt amp running two Kicker Comp R's in my 2003 Accord. I realized that my amp was drawing too much power from my car and I had a slight fear that my alternator might go out. So I purchased this wiring kit which is 0 gauge wire. Easy install. Now I'm able to turn my gain up a little more and don't have to dealneith dimming lights. I recommend this product.
Easy install.
1 out of 1 people found this helpful
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5 out of 5

Great Product

Written By BenD, Indianapolis, IN on Monday, May 05, 2014
Crutchfield Customer Review (What's this?)
This product took longer than expected to install just because of my vehicle type, Jeep, but once on, it works great.
Ease of use, Price, Works great
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4 out of 5

Very good, but I had to make adjustments

Written By Anonymous, St Amant, Louisiana on Wednesday, April 23, 2014
Crutchfield Customer Review (What's this?)
Everything was great the only thing I had to so was use the longer power wire as my alternator ground to be able to run the wire in the same place as the factory. And I just used the ground that was too short as the power wire. Other than that great overall.
It helped provide plenty more power to my car!
Had to switch out the power and ground wire. Worked good still.
1 out of 1 people found this helpful
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5 out of 5

Good Product

Written By Bob G, Palm Bay, FL on Saturday, April 12, 2014
Crutchfield Customer Review (What's this?)
Nice large gauge wire, no filler insulation, it's a true 1/0 gauge. Quite flexible given it's size. Installed it in my 1983 Camaro and the amount in this kit is enough to do the Big 3 three times over on my car. I literally have about 6' of cable left over, which is a great value in my opinion. This kit also helped out with some electrical issues my car had. The tiny little factory ground and charging wire wasnt big enough and as a result, my volt meter in the car would fluctuate each time my turn signal flashed. Turn on the headlights and A/C and watch the voltage drop well below 13v. Not anymore. I can crank up the stereo (with 250w amp), all the lights and the A/C on max and the voltage doesnt move. This kit certainly does it's job.
Tons of wire with pre-crimped ends. Great Value
Needs to be cut to length and new ends either soldered on or crimped which could be difficult for someone without proper tools.
1 out of 1 people found this helpful
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5 out of 5

Great Kit

Written By Wader935, Albuquerque, New Mexico on Sunday, December 01, 2013
Crutchfield Customer Review (What's this?)
Everything you need for the Big 3 upgrade. I had plenty of cable for my installation and had about a foot left over. Very flexible 0 guage easy to maneuver around and through tight places. One end of cable is already crimped with a ring terminal and shrink-wrapped so installation was a breeze. Although not soldered just crimped, i was skeptical if it would hold but it did. I did a pull test and crimped ring terminal did not budge. The cable is very thick and i really had to work to get it into my 0 guage battery terminal, and if you have the right wire cutters its easy to cut. Kit comes with extra ring terminals, shrink wrap and even zip ties to make the install look nice and clean. Overall i am very happy with this purchase and would definitely recommend this kit to anyone doing their own Big 3 upgrade. Thanks XS power and Crutchfield for the great price.
One end of each cable has a ring terminal already crimped and shrink wrapped.
Cable was difficult to get into my 0 guage battery terminal, but the bigger the better for this instance. I did get it to fit so not really a con just a pain.
3 out of 3 people found this helpful
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5 out of 5

high quality

Written By Hameen, San Diego on Monday, November 25, 2013
Crutchfield Customer Review (What's this?)
needed some wires for my high output Alternator 220amp this kit is rated at 250amp so it was perfect had all the correct tools to alter the size and mimic factory length. I would however suggest soldering the crimped wire before shrink rapping. great upgrade for your sound system.
everything is included and this is a very good price for what you get. The only way to get it cheaper is to build the kit yourself
not rated higher then 250
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1 question already asked

OK so I just bought a capacitor and it didn't help my lights that were dimming at all? How much would this benefit and would I have to but a high output alternator? I don't want to spend much money and if the capacitor is a waste I'll take it back for refund. I'm running 2 10 in Alpine type s Subwoofers with a Alpine m-1000 amp. [ Remington  Jan 09, 2014 ]
3 answers
  • This will allow more power to flow through your car. The wiring your car has now is very thin. The problem with doing the big three is the increase power flow to your alternator. Depending on how many amps your stock alternator is and how many watts rms you are going to be pushing will tell me more how important it is to replace your alternator [ PAUL   Jan 09, 2014 ]
  • Lose the cap they usually don't help much. It's hard to say how much you'll benefit but you will benefit nonetheless. it depends on your alternator size and current wiring. The big 3 will more than a cap probably would. [ Eugene   Jan 09, 2014 ]
  • Definitely get your money on the capacitor for the money you spend on a good capacitor you could by a good XS Power battery for under your hood and that would probably fix your light dimming problem. If you can afford to do the big 3 and replace your under the hood battery with the biggest Xs Power battery you can fit it will stop your dimming especially on a 1k amp. Hope this helps. Blessings! [ Darius   Jan 09, 2014 ]

For a more in-depth review and enhanced detailed information on the XS Power BIG3XP, please visit the Crutchfield website product page (/ISEO-rccbcspd/p_122BIG3XP/XS-Power-BIG3XP.html ).

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