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Best source for switched 12 V

64plybelvwgn

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I am in the process of re-wiring some of the circuits in my 65 Belvedere in which there is s '70 440. I am "running blind" a bit in that it is somewhat of a barn find as I purchased it from a senior gentleman who knew little about it...except that it was loud and I think he got more than he bargained for and decided to cut his losses. ( The wiring under the dash is somewhat of a cobbled " rats nest" . )

In any case, what would you consider to be the best source for switched 12 volts. I will eventually be putting in a 7-circuit Painless wiring module under the dash for gauges, tach, MSD ignition, etc. and would like to keep this as clean as possible while not having to do it twice.
( And as a very old senior myself - well it does happen! )

In advance than you for your help .

Ted
 
The wiring under the dash is somewhat of a cobbled " rats nest" .
Unless that 'rat's nest' is in too bad shape, to rebuild it, you might need to find a good used harness, or get a new one. On my 64, had two harnesses, and was able to build a good one up, from both.
Probably need to get a set of wiring diagrams...service manual will have them. Mainly so you can see how the various circuits are wired, including the switched one your asking about.
 
I am in the process of re-wiring some of the circuits in my 65 Belvedere in which there is s '70 440. I am "running blind" a bit in that it is somewhat of a barn find as I purchased it from a senior gentleman who knew little about it...except that it was loud and I think he got more than he bargained for and decided to cut his losses. ( The wiring under the dash is somewhat of a cobbled " rats nest" . )

In any case, what would you consider to be the best source for switched 12 volts. I will eventually be putting in a 7-circuit Painless wiring module under the dash for gauges, tach, MSD ignition, etc. and would like to keep this as clean as possible while not having to do it twice.
( And as a very old senior myself - well it does happen! )

In advance than you for your help .

Ted
As you are probably aware there are quite a few circuits that are powered by the "IGNITION" position of the ignition switch. The easiest and best way to resolve issues with switching and "loading" circuits is to use a relay where the relay is actuated by the " ignition on" position wire feed and let the relay supply the various circuits. Fusing can be done at he existing panel for the relay itself and all circuits switched on by the relay can be fused separately. I recently purchased an 7 fuse add-on panel from Painless and it included a built in relay to activate the panel's main 12 volt feed, 7 circuits rated to a max 15 amps ( although you can use any fuses to as low as 2 amps ) and it was prewired with about 6 feet of wire per circuit. This auxillary panel powers my stereo, ignition system, TBI unit, cooling and fuel pump relays, turn signals and Autometer gauges and tach. The last of the seven circuits I left blank for future add-ons. Great little solution. There are also 3 circuit panels for the budget minded who only need that many circuits.

http://www.painlessperformance.com/webcatalog/fuse7
 
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Unless that 'rat's nest' is in too bad shape, to rebuild it, you might need to find a good used harness, or get a new one. On my 64, had two harnesses, and was able to build a good one up, from both.
Probably need to get a set of wiring diagrams...service manual will have them. Mainly so you can see how the various circuits are wired, including the switched one your asking about.

Thanks for your reply. Rebuilding is an option I'll have to consider.
 
As you are probably aware there are quite a few circuits that are powered by the "IGNITION" position of the ignition switch. The easiest and best way to resolve issues with switching and "loading" circuits is to use a relay where the relay is actuated by the " ignition on" position wire feed and let the relay supply the various circuits. Fusing can be done at he existing panel for the relay itself and all circuits switched on by the relay can be fused separately. I recently purchased an 7 fuse add-on panel from Painless and it included a built in relay to activate the panel's main 12 volt feed, 7 circuits rated to a max 15 amps ( although you can use any fuses to as low as 2 amps ) and it was prewired with about 6 feet of wire per circuit. This auxillary panel powers my stereo, ignition system, TBI unit, cooling and fuel pump relays, turn signals and Autometer gauges and tach. The last of the seven circuits I left blank for future add-ons. Great little solution. There are also 3 circuit panels for the budget minded who only need that many circuits.

http://www.painlessperformance.com/webcatalog/fuse7

That looks like the best option. Thank you.
 
Didn't read everything ( lazy to do it midnight on the phone, maybe later ) but if just needed while engine running, blue RUN circuit wherever you needs it, engine bay ( ballast, volt reg, alt field if elect reg ) or even into the cab.

If doesn't matter run it while in acc, then acc into de cab... black wire from ign switch, or even fusebox.

If too much load, add a relay. BUT source it from alt post ( or ammeter black side ) for correct reading on amm, doesn't matter if triggered from RUN or ACC
 
Didn't read everything ( lazy to do it midnight on the phone, maybe later ) but if just needed while engine running, blue RUN circuit wherever you needs it, engine bay ( ballast, volt reg, alt field if elect reg ) or even into the cab.

If doesn't matter run it while in acc, then acc into de cab... black wire from ign switch, or even fusebox.

If too much load, add a relay. BUT source it from alt post ( or ammeter black side ) for correct reading on amm, doesn't matter if triggered from RUN or ACC

Thanks for your reply. Sincerely appreciated. I've acquired a service manual as a guide .
 
I have the 7 circuit Painless 70207 wiring harness on order. Looks like a good solution. Thanks for the tip. Ted

I was looking at the specs for the 70207. It should work fine with the items you mentioned, (gauges, tach, MSD ignition, etc.). It's the "etc." that's important. According to Painless the maximum total amperage for the 70207 is 40 amps. None of us have a crystal ball but if you decide to add, let's say an electric fan sometime down the road, the start surge alone, combined with the other existing devices will probably exceed that 40 amp maximum.
Like you said, you only want to do this once.
 
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