"The Big 3 Upgrade"

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HotRodPC

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Could be the counter person too mixed them up comparing parts with a customer's then wound up back into the wrong box, I used to see that working a Pep Boys when I was 17. That was a long time ago lol.

Or even someone who bought a part and returned it in the wrong box. Sometimes done on purpose to get a bigger refund. Crooks come in all shapes and sizes and they are very creative. Taking advantage knowing many counter people wouldn't the know the difference of a $2 electrical part in a $40 part box.
 

89Suburban

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Yap, that too. BOHICA, we get it from a sides, lol.
 

8T6K5

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Just added the final piece to this mod:

CS144 140A alternator:

Volt meter at idle, with just Big 3 mod:


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Volt meter at idle with Big 3 and CS144:


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Holding about 14v at idle.
 

HotRodPC

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That's not bad at all at idle. So you're still charging even at idle. 14.2 is about as high as you'd want to go, and 13.8 is actually better IMO, which might be about where you're at. Bulbs tend to burn out quicker if your voltage is to high.
 

89Suburban

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Nice. I can't wait til I get mine done. Mine is hurting in this cold weather idling too long with the headlights and heater on it drops down to around 12.
 

John81287

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Where is he best place to find the 1/0 wire? I've found a couple places for 6.95 a ft. Kind of expensive. Just thinking this might be a good idea for me while I'm doing the swap!
 

HotRodPC

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austinado16

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Excellent write up.

Did this upgrade about 2 years ago because while towing the pop-up camper with it's fridge in 12v mode, it's battery getting some charge, both a/c units running and sometimes having sections of road that require daytime headlights, I was seeing voltage down in the 11-12 range. Not good. I went with some large gauge stuff, including the run from the starter solenoid to the junction on the firewall. Made a big difference.

I'd been doing this mod on all of our cars for years, after working on German cars that suffered from small cable syndrome right from the factory. Back in the mid-90's the Volkswagens in the Los Angeles area were dying on the freeway, in the middle of the day.....with dead batteries. I was a tech at the local dealer at the time, but had come from an independant German shop, where we'd been doing the mod for years. It was all new to the dealers, and VW eventually came out with a recall campaign to replace the cable from battery to starter solenoid (alternator jumpered from there). The factory cables were actually getting so hot that they wouldn't flow electrons. I got a kick out of the recall notice, because I'd already been doing it to their cars for years.
 

89Suburban

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I did the final step this morning...added the extra wire from the alt + to the battery+. Truck fired up in about 2 revs, apposed to the normal 5 to 7 for a cold start after sitting over night.
Ran like a new vortec after that.

I think I have a ton of welding cable on my dad's arc welder that has been collecting dust, I can probably use that. Just got to get some lugs to solder on. I think this will solve the problem I been having lately with cold starts. Nothing wrong with the battery or starter.
 

HotRodPC

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I'll sure be glad when I get to do this to one of mine !!!
 

89Suburban

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Well I bought 5/8" lugs yesterday and they are too small for the 1/2" welding cable I have so I got to make a trip to Home Depot and see if they might have something and they should have the 1/2" shrink tubing I would imagine. Did anybody do the battery to starter cable? That looks like a bitch. Lot of clamps on it along the oil pan bolts. I'll try to at least knock out the alternator and ground wires tomorrow.
 

JJFz6r

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Hello gentleman, I am not too familiar with my truck wiring and am having a hard time finding some of the wires mentioned for this upgrade. I have a 400 small block, I have the neg to chassis ground and pos to starter wire, but there isnt a pos to alternator, all that seems to connect to the alternator is 4 small wire together. Also having a hard time finding the engine to ground. I know this might seem like a stupid question but if anyone has information on this it would be great, I can also snap a couple of pictures to clarify if needed
 

HotRodPC

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Many times engine to ground never gets hooked up back up, but it goes toward the back of the motor bell housing bolts to the firewall. You should have a 10gu or so red wire off the alternator, then a 2 wire plug. It's grounded through the brackets to the block.
 

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