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TheRoaringEagle
05-06-2005, 07:18 PM
How do I wire the Alternator correctly? It is a Delco Remy 10si model that puts out ~60 amps. So I have the double spade connector plugged in factory like, with the red wire connecting to the battery post on the alternator. And then I have a charging wire connected from the batt. post on alternator to the positive post on the battery. Is this correct? Or am I supposed to wire it to a main junction post where all the accesories are?

I just got a replacement alternator (previous one lasted 1 month) and it doesn't SEEM like it's charging like usual. It keeps the car around 13 volts and then I turn on the lights and it goes down to 11.

Zefhix
05-06-2005, 11:34 PM
How do I wire the Alternator correctly? It is a Delco Remy 10si model that puts out ~60 amps. So I have the double spade connector plugged in factory like, with the red wire connecting to the battery post on the alternator. And then I have a charging wire connected from the batt. post on alternator to the positive post on the battery. Is this correct? Or am I supposed to wire it to a main junction post where all the accesories are?

I just got a replacement alternator (previous one lasted 1 month) and it doesn't SEEM like it's charging like usual. It keeps the car around 13 volts and then I turn on the lights and it goes down to 11.

It depends on the rest of the wiring and what kind of load is put on the alt. If its just ignition, headlights and light stereo 60 amps is fine. Anything else like heavy stereo, electric fans, water pump, windows, etc. and you need to step up to a good 100 amps or more. The way you wired it is correct although some like to take the other spade connection (marked F for 'field" I believe) and run an ignition hot to it instead of the constant on the back of the alt where the main batt connection already is. Essentially its a switch that tells the alt to work so wiring it hot all the time just means it's on all the time. No biggie, I've run two cars like that with no problems.
No, the real issue, though, is going to be the guage of the wire. Is the batt in the trunk? You need to run at least a 8 guage if the batt is in the engine compartment and I recommend 2 guage (no it's not overkill) if the batt is in the trunk, as your main positive terminal to starter selenoid should be 0 guage if it's in the trunk anyway. Or you can run the main line from the alt to the positive terminal on the starter where the batt meets it if it's in the trunk as well. Also, remeber that no matter what, the positive wire can only flow as much current as the negative can so if you are running 2 guage to the starter selenoid but the ground on the batt is 8 guage, your positive terminal can only flow the amperage of the 8 guage despite the fact it's thicker. Hope this helps and doesn't confuse you. :cool:

deronsorrell
05-07-2005, 01:36 AM
I would suggest not hooking the voltage sensing wire directly to the alternator output because the alternator will not compensate for voltage drop through the system. You might want to take a look at this article by Mark Hamilton of M.A.D. Enterprises about wiring alternators and remote voltage sensing. http://www.madelectrical.com/electricaltech/remotevoltagesensing.shtml
I found it helpful.

I called and order a couple of things from M.A.D last summer and Mark (the owner) actually answered the phone and we talked for a few minutes. He seems like a great guy and he was very helpful.

Just my two cents.

Deron

TheRoaringEagle
05-07-2005, 09:11 PM
It's charging a little better now that I've replaced the charging wire with a shorter 8 gauge one. And so my alternator is on the driver's side and the battery is moved back up to the passenger side. I looked at all my Camaro Performers magazines and tried to find the best way to wire it. I couldn't find anything. So right now the charge wire runs from the alternator down it's top arm bracket, across the intake and head, and then finally crossing over to the battery post. It looks terrible. What's the best way to wrie my baby without it looking ugly and using long cable? Thanks!

David Pozzi
05-20-2005, 09:45 AM
Read the M.A.D article, it's REALLY GREAT!

Run the charging wire and alt sense wire to the main load lug at the horn relay, not your battery. Running it to the + battery terminal hits the battery pretty hard at times especially with a high amp alternator, and the main load lug is where your accesories take off and that's the point where you want full voltage.
David

paul67
05-21-2005, 11:24 AM
Any chance of a diagram being posted as when I put my fan and lights on I get a volt drop on charge gauge from 13.4 to 11.6 .
paul67

gmachinz
05-22-2005, 05:50 AM
The best way I've found to measure voltage drop is to just probe the actual +12V lead to the fan or light, etc. Ideally, you want as close to 14V as possible. By utilizing a +12V junction which runs off the main charge post on your alternator and then running your accessories off that, you get the best voltage as can be expected. Never run accessories off the battery except in special circumstances. If you have a CS style alternator or newer, run the voltage sensing wire to the same terminal juntion that shares the accessories. For example, I would suggest an 8-guage wire from the charge post to one side of the junction, then run your voltage sensing wire along with your other +12V accessory wiring on the other side, that way the alternator will detect the additional load whenever you turn on your fans, headlights, ect. If you want some help, I can draw up a quick wiring diagram if you want. Email me and I'll send you one so you kinda have an idea to go from, you'd need to include everything you're running for accessories and type of alternator. Right now I'm doing stereo builds that require the use of two batteries w/iso's and 200-amp alternators! I'm double-stacking diodes on the outside of the 6" case alternators for better cooling....crazy stuff! -Jabin