Bulkhead bypass vs ammeter bypass

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remytherat said:
I would like to run a 90 amp alternator and I’m wondering whether I should just bypass the charge wires in the bulkhead or if I should bypass the ammeter entirely. Electrical draw will not be huge, just electronic ignition, headlights, electric fan
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MadElectrical.com - Electrical Tech This is a good spot for advice, I’m going to follow their advice on my build.
 
Run a protected direct charge wire from alternator to starter relay and leave the OEM wiring in place. Make darn sure the bulkhead connector is in great shape. Mad is OK, I perfer to not cut up harnesses. The cutting can be avoided.

Those packard terminals I'll use a 56 as an example, you don't really want to run more than about 20, maybe 25 amps on a spike across those connectors. A 60+ amp load from an alternator is not kind to bulkhead packard connectors.
 
RLF Cuda said:
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The battery terminals are first rate. I used the military grade terminals with side studs for connecting wires. The restoration shop built power and ground wires for a 80A alternator. The alternator power does run partly through the firewall so the ammeter shows some charging, but the bulk of the power runs through a 10Gauge wire with fusible link directly to the battery. Other than the cheap Chinese alternator from O'Reilly which I want to replace, all works well.
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Very reasonable, too! Thanks!
 
crackedback said:
Run a protected direct charge wire from alternator to starter relay and leave the OEM wiring in place. Make darn sure the bulkhead connector is in great shape. Mad is OK, I perfer to not cut up harnesses. The cutting can be avoided.

Those packard terminals I'll use a 56 as an example, you don't really want to run more than about 20, maybe 25 amps on a spike across those connectors. A 60+ amp load from an alternator is not kind to bulkhead packard connectors.
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^^^ This right here! @crackedback is right - leave all the underdash wiring in place. Just run a battery charge wire to the B+ terminal on the starter relay. Protect the wire with a "4 number larger" fusible link (ie. 6ga wire with a 10ga fusible link). Presto and done!

The battery charge current will go straight to the relay and not the tortuous path through the bulkhead connector. The ammeter will now no longer show much, if anything, as there should be very little current flowing through it.
 
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Demonx2 said:
The battery charge current will go straight to the relay and not the tortuous path through the bulkhead connector. The ammeter will now no longer show much, if anything, as there should be very little current flowing through it.
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I take the ammeter out of the equation as well by linking the red/black wires back there together. Machine screw and ny-lock nut work great!
 
Spadman said:
LOL; I saw in one of the Slant SixDan quotes that someone “sooner or later would mention MAD Electrical”. I guess I’m that guy. I was impressed with their site and didn’t know any better.
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Does the mad approach work, yes it does. Are there other ways to skin a cat, certainly.

I build those charge wires and never use OEM 10ga wire as Mad suggest. Minimum sizing is 8ga. Dan's approach of 2 10 ga wires is equivalent to a single 6ga wire. Larger wire, better transfer, less voltage drop across the line.
 
crackedback said:
Does the mad approach work, yes it does. Are there other ways to skin a cat, certainly.

I build those charge wires and never use OEM 10ga wire as Mad suggest. Minimum sizing is 8ga. Dan's approach of 2 10 ga wires is equivalent to a single 6ga wire. Larger wire, better transfer, less voltage drop across the line.
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Thanks. I want to learn all I can because I’m close to the wiring phase of my build.
 
remytherat said:
I would like to run a 90 amp alternator and I’m wondering whether I should just bypass the charge wires in the bulkhead or if I should bypass the ammeter entirely. Electrical draw will not be huge, just electronic ignition, headlights, electric fan
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When I put my high output alternator in my 64 I ran directly to the +ve side of the starter. Ammeter always shows discharge, put a voltmeter in your system to monitor if you're charging. I still haven't!
 
I recently did the MAD electrical upgrade of my system found Here .
I used 10g wire as recommended by them, and the wires it replaced were probably only 12g. I am running an Autometer volt meter so I know what the system is doing and dont miss the factor ammeter. I also redid the factory welded splice by running all affected wires into a Wago wire connector(these little Wago connectors are amazing) rated for 10g wire, no need to solder and cleaned it up very nicely!
Yes, its a pita because you have to remove your dash bezel to do this, but Im glad I did, my electrical system is working as it should, and Im confident that my ride wont burn down and take my garage with it. I also found a few suspect connections along the way that I fixed up as well.
I did all this because I had an issue with my electrical system(smoke was involved) and @67Dart273 recommended this to me.
Im glad I took the time to do it.
 
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