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Wire Direct From Alternator To Battery


Well-Known Member
Local time
10:11 AM
Jul 2, 2012
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upstate ny
Hey guy's I've been having problems with my charging system since I installed my new 440 in my 73 roadrunner. I am running an Edelbrock E street EFI with dual electric fans connected to relays off the battery that use signal wires from the ECU to trigger them. Ever since getting it all up and running the volt gauge on my EFI tablet would only ever show maybe 12.6v at cruise and sometimes under 12v while idling. When I rebuilt the engine I put a new accessory kit on the engine so a brand new alternator and I also replaced the old voltage regulator with a Mopar performance unit. I've also installed led headlights and made a new harness using the old headlight wires as triggers for the relays wired directly to the battery. The car ended up leaving me stranded at a gas pump when it wouldn't restart so I decided get it figured out. I did a lot of reading and read that the old wiring going through the ammeter was probably the culprit and while reading I found that some people run a wire directly from the alternator to the battery which supposedly relieves some stress off the original wiring and allows for full charge to battery. I tried this yesterday and it actually worked great I'm at 13 volts idling and 13.7 to 14 while at cruise now even with headlights and a fan running. My question is is this ok to leave it like this in the long term? The only thing I noticed is the ammeter reads at about an 8th of an inch under discharge now.
Sounds like excessive voltage drop in the charge path and incorrectly added loads at the battery while running an ammeter. A direct wire from the alternator to the battery without any circuit protection? There has been a great deal of info posted here on this subject.
Run a fusible link wire in there to protect from any surge that might happen. It's a little added insurance.
Don’t do that in a way that parallels the existing fusible link, will increase the cut off current by almost a factor of 2. Puts all of the factory unfused circuit wiring at risk of burning in the event of a short.
That’s a lot of current potential for the factory 12ga un-fused charge circuit wiring should a short occur.
I'm going to be honest I do not understand what you are getting at. From what I read by running this wire there is less going through the original wiring as it shares part of the load. You may have to dumb down what you are getting at a bit more if you want me to understand lol. I do plan on fusing the wire like I stated above.
What is the alternator Amp output. That is what to fuse the wire at going to battery.
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