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Discussion Starter #1
Hey Friends- I'm helping a buddy get his 65 Fastback back on the road. He's planning to add dual electric fans, a one wire alternator, and a Vintage Air Surefit unit. We're contemplating upgrading the fuse block to accommodate the modifications versus adding inline fuses to wires run off the ignition switch. Has anyone done this? Is it just a matter of unsoldering the wires from the old fuse block and re-soldering them to the new one?
He's also not opposed to replacing the whole wiring harness with an American Auto Wire harness. There is an existing harness already in the car. Any thoughts?

Mike
 

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What makes MORE sense than "upgrading" the existing fuse panel is to add an auxiliary fuse & relay block in the engine compartment to keep the full 12V power runs short. The cooling fans don't require any wiring in the passenger compartment so that's one issue. Neither does the alternator and there's really no reason to add a fuse unless it's AT the alternator output terminal. The A/C unit should have a dedicated, relay-triggered, battery feed so we're talking about just an ignition "trigger" wire which, again, doesn't need to come into the passenger compartment.

Now, as far as "upgrading" the existing fuse block... I can't say it wouldn't make sense to replace the box with something like the one shown below.... lots of extra capability to grow. Thirty Five bucks on Amazon.

767353
 

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My factory under-dash harness had been replaced and I just didn't want to convert the whole car to a modern harness. So to add a couple circuits, I added this aux harness from painless.
This would be good for adding a few things that need to be inside the car, but for fans and light relay circuits you should get something for the engine bay.

 

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Discussion Starter #6
We discussed an auxiliary fuse block but he likes the idea of just having one fuse block. He wants to keep things "uncluttered" as much as possible. This was partially why he's considering the AAW kit. Its already set up for everything he wants plus it replaces the 55 year old wiring.
 

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We discussed an auxiliary fuse block but he likes the idea of just having one fuse block. He wants to keep things "uncluttered" as much as possible. This was partially why he's considering the AAW kit. Its already set up for everything he wants plus it replaces the 55 year old wiring.
my only complaint about the options for new complete harnesses are that they bring the headlight and fan relays into the underdash.
we really need an option similar to most modern cars that has two separate fuse/relay boxes. One up near the battery for headlights, fog lights, fans, horns and EI and EFI. Then a separate underdash harness for all the interrior stuff like gauges, ac, power windows etc.

I don’t hear much about it, but the RCR/superlight kits come with a wiring kit, used to me called isis, I think they changed their name to Infineon, or something like that. Their kit is modular and allows for separate control hubs. Even a rear power bank for electric fuel pumps etc.
 

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I am doing much as Bart suggests above. Wiring starts tonight. I bought this one:


Relays will serve: low beam headlights, high beams, horn, fan and leave me a spare for a two speed or dual fan should I upgrade. The box will be fed by by 6 ga wire that goes to a distribution block. Individual circuits will be fed through fuses and relays off that distribution block. Relays will be triggered to tapping into the stock harness. New 12ga wire will run out from relays to serve lights, horn and fan. I bought a 150amp circuit breaker to protect the 6ga wire and distribution block.
 

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I am doing much as Bart suggests above. Wiring starts tonight. I bought this one:


Relays will serve: low beam headlights, high beams, horn, fan and leave me a spare for a two speed or dual fan should I upgrade. The box will be fed by by 6 ga wire that goes to a distribution block. Individual circuits will be fed through fuses and relays off that distribution block. Relays will be triggered to tapping into the stock harness. New 12ga wire will run out from relays to serve lights, horn and fan. I bought a 150amp circuit breaker to protect the 6ga wire and distribution block.
If you can can you start a post on how and what you did wile doing this?
 

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That looks like a really nice option!

For my recent project, I 3d printed my own 3xRelay+fuse mount to control High/Low & fog lights. If I were to do it again, I would add relays for horn and electric fans.

That box looks like a great option. (y)

I am doing much as Bart suggests above. Wiring starts tonight. I bought this one:


Relays will serve: low beam headlights, high beams, horn, fan and leave me a spare for a two speed or dual fan should I upgrade. The box will be fed by by 6 ga wire that goes to a distribution block. Individual circuits will be fed through fuses and relays off that distribution block. Relays will be triggered to tapping into the stock harness. New 12ga wire will run out from relays to serve lights, horn and fan. I bought a 150amp circuit breaker to protect the 6ga wire and distribution block.
 

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I added a secondary fuse box in my mach, best thing I ever did. I run all my accessories through it and never touch original wiring. I used a painless wiring unit, 7 circuits. Some are switched and rest are constant power.
 

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I added a secondary fuse box in my mach, best thing I ever did. I run all my accessories through it and never touch original wiring. I used a painless wiring unit, 7 circuits. Some are switched and rest are constant power.
Same thing I did..
 

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Do you guys have any pictures of how you installed the secondary fuse blocks?
I welded a small bracket to the support bar that’s just to the right of the radio hole on my 67.

this pic is from a very low angle. Sort of like a new car, it’s almost impossible to see unless you get low and look up under the dash, from the passenger side.
767393
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