"The Big 3 Upgrade"

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HotRodPC

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I'm suprised this hasn't been added to GMSB yet. I've been going to do a write up on this for some time now, but haven't gotten to it. So I'll just assemble the information from a few different sources and if someone wants to do this upgrade to their square then post up your pics as you complete it, feel free to do so.

This upgrade is most commonly known in the Car Audio world for those who want to add a big heavy audio system. But, it's also great for any off roader who's running high wattage off road lighting a powerful winch or air compressor for Air Lockers or Air Bags. It's also good for those who might be running a big power inverter to operate power tools off of their truck at a work site where there is no electricity.

This system also works well and goes hand in hand with a battery and alternator upgrade to make sure you have the best possible electrical, starting and charging system on your vehicle.
 

HotRodPC

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Please be sure you read and understand this entire instruction before you begin.

Definition: the "Big Three" upgrade means improving the current capacity of three cables: 1) alternator positive to battery positive, 2) battery negative to chassis, and 3) engine ground to chassis. Some people replace the factory wiring; others add additional cables to the factory wiring. This instruction is to add cables to existing OEM wiring.

Parts and Tools:

As a minimum, you will need to purchase the following:

• Sufficient length of high-strand count high capacity power cable.
- The length required differs for every vehicle. You can measure the length of the existing cables and buy the same length, or contact your dealer or a mechanic and ask, or sometimes you can look it up in a manufacturer's wiring book, or guess. If you guess, make sure you over-estimate and buy too much.
- High strand count cable is more flexible and more reliable than low-strand count cable. Never use solid-core wire in a moving vehicle as it will eventually break.
- The gauge of wire you need depends on the total current draw of your audio system, and/or the current generating capacity of your alternator. Never use smaller cable that you used to power your amps; never use smaller cable than what already exists in your vehicle; never use smaller cable than the generating capacity of your alternator; never use smaller than 4 AWG and 1/0 is best.

• 6 ring terminals or lugs of the appropriate size for the cable chosen. Two of these need to be large enough to fit over your battery posts, or appropriately sized to bolt onto your existing battery terminals.
• 1/2" or 5/8" shrink tubing (or some other form of permanent electrical insulation. Tape is NOT recommended.)
• Cable ties (plastic zip ties.)

• Wire cutters large enough to handle the cable you choose.
• Crimpers large enough to handle the connectors you choose.
• Soldering iron or gun.
• Solder.
• Scotch brite and/or a small wire brush.
• Heat gun.
• Safety razor blade or other cable stripping tool.
• Heat gun for shrink tubing.
• Wrenches for removing bolts in your vehicle.

Procedure:

1. Make sure your engine is completely cool before beginning. Identify the three cables being replaced. Make sure you can reach both ends of all cables. NOTE: the engine block to chassis cable may be between the engine and the transmission, or connected to the transmission and the fire wall, and is often an un-insulated flat braid cable.

2. Determine the lengths of cable needed to reach between the three locations being upgraded. Be sure you measure with a flexible tape and record the total length along the path you intend to install the cable. You do not want your cables to be pulled tight between any two locations as things move and vibrate as you drive. Be sure to include at least 1 inch extra for slack. NOTE: there is no reason to copy the existing wiring layout in your vehicle unless you want to. Also, be sure that the path you choose does not follow or lay across anything that gets hot, like exhaust parts, or anything that must move, like throttle linkage.

3. Cut your new cable to the three proper lengths. NOTE: some people like to use red cable for positive and black cable for negative. Doing this is completely up to you and is nice, but not necessary. You can use cable with any color insulation you like.

4. Strip each end of all cables to the proper length for the terminal lugs being used. NOTE: after full insertion into the lug, a small "band" of bare wire is usually seen between the back of the lug and the beginning of the cable insulation.

5. Begin at any one end and insert the stripped cable into the lug. Make sure it is fully inserted. Crimp the connector to hold the wire in place. NOTE: crimping large cable can be difficult. The intention here is not to make the crimp the sole means of holding the wire, but only to make sure the lug does not slip around during the soldering phase. I do NOT recommend using hammers or pliers or vices to crimp the connector as over-crimping can break the strands of the cable, reducing the current carrying capacity. Do not over-crimp.

6. You may need to use a vise or some other set of "helping hands" to hold the cable while you solder it. Heat your soldering iron and place it on the connector (on the lug side) barrel. Hold a piece of solder against the tip of the iron and melt the solder into the strands of the cable. Use sufficient solder to fill the connector and completely cover all strands of the cable.

7. Repeat the above steps on each end of all three cables.

8. After the cables have completely cooled, cut a piece of shrink tubing long enough to cover the soldered barrel end of the lugs and reach about 1/2" onto the insulation of each cable end. Slide this over each lug and use a heat gun to recover the tubing in place.

9. Disconnect your battery, starting with the negative cable first then the positive cable. Discharge any caps you may have in the system.

10. Begin adding your new cables along side the existing ones. I usually begin with the alternator positive cable. Locate the output stud on your alternator and remove the nut. Slip the new cable onto the lug and replace the nut. There is no need to disturb the existing cabling. Route the new cable to the battery and position it to connect to the positive battery post (or connect it to the positive terminal on the OEM wiring) but do not connect the battery yet.

11. Secure the new cable in place by using cable ties every 6 to 8 inches. Secure the cable to cool non-moving parts!

12. Locate where the negative battery cable attaches to the vehicle chassis. Remove this bolt and the OEM battery cable, and clean the mounting area of the chassis using scotch brite and/or a wire brush. Make sure there is no dirt, rust, paint, undercoating, etc in this location. You want bright shiny metal. Connect both your new ground and the OEM ground back to the chassis. NOTE: Some people like to create a new ground location by drilling into the chassis and using a bolt with star lock washers for the new ground cable. Route this new cable back to the battery and position it to be attached, or connect it to the negative terminal. Do not reconnect the battery yet.

13. Secure the negative cable using cable ties every 6-8 inches. Again, don't tie it to anything that moves or that gets hot!

14. Disconnect the engine ground strap at both ends. Using the wire brush or scotch brite, clean both the engine block and the chassis as you did for the first ground strap.

15. Line up the lugs on both the OEM ground strap and your new ground cable, and use cable ties to secure them to each other. This is much easier to accomplish in your lap or on the floor than it is while lying under your car or hanging upside down in the engine compartment. Reinstall both cables at the same time using the factory bolts.

16. Double check to make sure all bolts are tight. Be careful not to over-tighten them as you don't want to strip anything! Also, on some factory alternators it is WAY too easy to twist off the positive output lug. If you break it off, well hell, you really wanted a high-output alternator anyway, right? It is also a good idea at this point to measure resistance of the new cables. Take an ohm reading between the battery end of the new ground cable and the engine block. It should read less than one ohm. Also check between the alternator bolt and the disconnected positive battery terminal, which should also be less than one ohm. If you read too high resistance, double check all connections and make sure you do not have something cocked sideways or hanging loose.

NOTE: Realize that the "absolute ground" of the electrical system is not the battery negative terminal or the vehicle chassis, but is the case of the alternator itself. This is why perhaps the most important cable among the Big 3 is the engine ground strap, as this is what connects the alternator ground to the vehicle's chassis. Be certain the resistance between the alternator case (the engine block assuming the alternator is properly bolted to the engine) and the battery negative is minimized.

17. When you are sure you are done and anything in your system that you may have disconnected are re-connected, clean your battery posts and reconnect the positive battery terminal first, then the negative one.

18. Start your vehicle. Examine the engine compartment and make sure none of your cables are getting hot or are vibrating or shaking around. If they are vibrating too much you may need to relocate them or use more cable ties. If you see smoke, immediately shut off the car and disconnect the battery.

19. Assuming all looks good, take a voltage reading at your accesory to ensure you read at least 13.8 volts. This indicates a properly operating charging system.
 

HotRodPC

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Here is a couple of generic boring videos, but they are informative and actually show you the steps to take aloing with some precautions.

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Stroked

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Good stuff! Every vehicle should have this done.
 

guitarfreak235

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ive actually been working on this myself! im not sure if you mentioned this in the post, didnt read the whole thing, but you can buy battery posts that are threaded on both sides and come with a nut. this way you can add the extra wires cuz the stock ones wont cut it.
 

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Been looking to up my alternator from an OE 105 (maybe 110) to a 130+. Perfect time to do that mod. Looks like a difficulty level of 2 on a scale of 1-10.

Never heard of i tbefore, thx.
 

guitarfreak235

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Been looking to up my alternator from an OE 105 (maybe 110) to a 130+. Perfect time to do that mod. Looks like a difficulty level of 2 on a scale of 1-10.

Never heard of i tbefore, thx.

what do you plan on using it for?
 

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I need to do this, just to help the original factory systems at least. And it's cheap and easy. I probably got half the stuff laying around in the garage.
 

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what do you plan on using it for?

Help with the 2 AMP's already in the truck that run 2 12's and 4 door/panel mounted speakers (may add set in rear someday), 4 Hella 550's, all new lighting (use my Hi Beams as DRL's) and anything else that may come up......winch?
 

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You may notice a better idle with this mod as well.
 

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You may notice a better idle with this mod as well.

Which was one of the reasons I was looking to replace the alt. Then figured I may as well up the amps. Then I saw this. Battery is brand new too, so it all should make a huge difference.

Like HR and I talked about changing suspension components in pairs, I figure if Im going to pull the alt, for a few extra $$ do this at the same time and know that; that project wont have to be repeated for a loong time.

Some may consider it overkill, and I agree at a certain point people do get crazy. I know that the wires and connectors can be had for $40-$50 plus another $20 if you do the in-line fuse. $50 to know that if I ever want to add another accessory I dont have to worry about the draw.

No diff than a motor.
 

HotRodPC

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I intend to do it to all my 4x4's and since it's an easy mod probably the Box Van if I keep it too.
 

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Help with the 2 AMP's already in the truck that run 2 12's and 4 door/panel mounted speakers (may add set in rear someday), 4 Hella 550's, all new lighting (use my Hi Beams as DRL's) and anything else that may come up......winch?


well you probably dont need a new alternator for amps unless you plan on something crazy, im runnin 250 watts now with absolutely NO voltage drop or dimming. i wouldnt replace the alternator unless you really do need it. but with that other stuff you may need too
 

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Already ordered the cable/connectors. May have to hold off on the alt for a bit. Did F/R brakes today, both front calipers shot. Just grabbed a set of reman ACD from Rock Auto.

BS about the core on a caliper, was like $25ea. Will just put that $$ when its returned towards the alt
 

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i'll probly do this and also run it under my seat to were i will have the amps(mabey run 2 wires. 3k+ watts might draw a bit) then on top of that. i still want to run a few KC's.
 

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