[mybad69]

I have read the tech archive and have purchased the CS 130 alternator to install on my 69 396 chevelle. I have followed the disassembly process for the wiring and found it to be exact in detail. My question is Why do all of these companies sell the alternator conversion kit with "over 60 amp alternator" do I need to upgrade any on my factory harness to carry the added amperage???? Also My battery is in the trunk And I am running power from it to the starter, from the starter to the power point on the firewall. Does this change anything or does it hurt the conversion from the factory style specs???

 

[Hoptup32]

The alternator companies seem to see a need for the higher amp alternators today, because a lot of high amp accessories are being utilized on street performance cars that weren't necessarily stock at the time. Such as, electric radiator fans, power windows, stereo amps, etc.

To be safe, if you upgrade to a larger amp alternator, I would upgrade the output feed from the alternator to a 6 or 8 guage wire all the way back to the starter, including to the power point on the firewall.

Even though you may not actually require 60 amps or more under normal driving conditions, its nice to have the larger gauge wire just to assist the recharging of the battery since its a longer run to the trunk.

 

[mybad69]

[No message]

 

[mybad69]

So I need to use either a 6 or 8 gauge wire from the back of my alternator to the power point near the radiator, then from the radiator point to the battery??? Will this be all that is left for me to do?? If I already have 2 gauge wire from my starter to the battery. Can I just go from the power point to the starter without running another to the batter???

 

[John_Muha]

Can I ask why you went to such a large alternator? What did you add to the car?
The battery is only going to take what it wants, not what the alternator is capable of putting out. Bigger does not mean better.
If you haven't added anything to the car, you may have to increase wire size only because you moved the battery further away from the alternator.
Measure across the battery terminals while the car is running. 14 volts is a good reading.

 

[mybad69]

My alternator finally died while driving home the other night. I wanted to upgrade to a newer more powerful alternator, due to me wanting to add dual electric fans, and ac at a later date. I now have a MSD 6al box and holley blue fuel pump, and with such a (small??) load, I continually drove around at night with my lights continually fluttering and fuel pump running high then low,high then low. I'm not an electrical genius by any means but I thought that the 2 gauge wire from the starter to the battery was enough to transfer voltage. My wires from my alternator go to the power point and then to the starter. Shouldn't this work or have I flubbed it up????

 

[Hoptup32]

The output wire from the alternator to the power point and then to the starter is fine. The 2 gauge wire to the battery in the trunk should be sufficient also, as long as its not 2 guage welding cable.

I also hope that the alternator that just died was your old one and not the CS130? If it wasn't the CS130, then wire it up and do as John suggested, check the voltage at the battery terminals while the engine is running to see if the new alternator is operating correctly.

 

[John_Muha]

Originally posted by Hoptup32:
The output wire from the alternator to the power point and then to the starter is fine. The 2 gauge wire to the battery in the trunk should be sufficient also, as long as its not 2 guage welding cable.

I also hope that the alternator that just died was your old one and not the CS130? If it wasn't the CS130, then wire it up and do as John suggested, check the voltage at the battery terminals while the engine is running to see if the new alternator is operating correctly.

The only wire that matters is the wire from the the alternator to the horn relay. Making the wire from the horn relay to the starter terminal isn't going to help unless you are running a drag car.
Again check to see if the battery is being properly charged 'cause you moved it further back.

 

[mybad69]

OK so I think I have it now. The wiring is fine unless there is less than 12 volts at the battery posts. If there is a problem run a thicker gauge wire from the alternator to the battery. I'm at work right now and not currently able to try everything out I have ask everyone about. Thanks everyone for the input. My final question is though....Why can't you use welding cable from the battery isn't it thick enough???

 

[John_Muha]

Not quite. Because you moved the battery further away from the alternator, the wire between the two is now longer. The longer wire looses more volts than a shorter wire. One way to fix this problem is to go to a larger wire because the length is longer.
A 12 volt battery will not charge by putting 12 volts into it. You need around 14 volts to "push" the voltage back into the 12 volt battery. When the car is running, the alternator puts out around 14.5 volts. You need to see around 14 volts, across the battery terminals, when the car is running. Otherwise the battery won't stay charged.

 

[ehjorten]

Question John...

I just did this upgrade on my '69. What gauge wire should I use for the feed from the alternator back to the battery (battery in stock location)? Is it really necessary to run that wire all the way to the horn relay? Seems like a long length of wire to run, when I can connect inside the harness at a much shorter length.

Thanks,

 

[John_Muha]

Originally posted by ehjorten:
Question John...

I just did this upgrade on my '69. What gauge wire should I use for the feed from the alternator back to the battery (battery in stock location)? Is it really necessary to run that wire all the way to the horn relay? Seems like a long length of wire to run, when I can connect inside the harness at a much shorter length.

Thanks,

Not sure how to answer the question. It depends on what you added to the car, such as a large amplifier, and where you hooked those items up to. If all you did was change the alternator size, there's really no reason to change the size of the wire.
The wire may need replacement because it's old, but that's another issue.