High Amp Alternator and Accessories Questions

jrcr_15

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Hello,

Sorry for the long read, but I am hoping to get some insight to help me out with the major electrical revision I am making to my Duster.

I purchased a high amp Power Master alternator to feed the electrical needs of my car. The “Proof of Performance” slip that it came with, states it puts 182 amps at idle, 195 at cruise and 238 at the top end.

Electircal add ons in addition to stock accessories include:

- Electric water pump

- Dual Spal fans

- Fan controller unit

- Fitech dual quad EFI

- Dual Fitech in tank electric fuel pumps

- MSD Ignition

- Autometer RPM tach

- Indicator lights: oil pressure, shift light

- Snow Water Meth injection system

- Stereo

- The famous crackedback headlight relay kit

I also purchased a new painless wiring harness to replace the 50 year old harness in the car as it was starting to show its age in a few spots. With the new harness installed, there will be no factory bulkhead connectors in use whatsoever. Additionally, I am making use of a voltmeter instead of the ammeter.

I am a bit stuck on a couple of items and seem to be going in circles trying to answer my own questions, so I wanted to get some advice as I may be misinterpreting the information I need or not asking the right questions.


Does this seem practical ?

High amp alternator runs to fuse block 1 which has a 225amp fuse, via 2 awg to the starter relay.

My main question that I want to get clarification on is when I get to “Fuse 2”, previously the fusible link that would feed the interior.

- Should this also be 2 awg from starter relay to Fuse 2?

- What size should fuse 2 be? 225 amp, the same as fuse 1?

- From “Fuse 2” to the interior of the car should this be 2 awg also?


I plan on adding a second fuse/relay panel dedicated entirely for the water pump, fans etc in the interior of the car to keep my engine compartment looking less cluttered.

I plan to tie this info the key on ignition source as most of the accessories I mention are key on power.


Also see my schematic. Any insight is appreciated as I am not electrical expert by any stretch. Thanks in advance.

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67Dart273

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Fuse 2 needs to protect the wiring --needs to be sized appropriately for that and I would not power fans and other heavy stuff off "downstream" of the interior. Maybe add "fuse 2 and ""2a" What you really need is something like modern car distro bloks where you can have a ?? no4 or so feed with a master fuse link and then individual fuses from there

If you are killing stuff through the ign switch, power down the relay coils, not the main feeds to the relays.
 

jbc426

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I found there is absolutely no need to run high amp power through the bulkhead connector. If you need to, use a separate bulkhead pass through that's rated for that amp load.

I run my alternator cable to the factory relay lug on one car with less electrical demand, then a second cable continues down to the starter. On my other car I use a distribution lug to send the power where needed. I've found that Marine Grade and high end stereo electrical components and wire are of much higher quality than I can find from auto parts sources. The fused distribution blocks are very cool from places like West Marine.

Use quality relays on every high amp draw circuit. keep all high amp draw feeds out of the bulkhead connector. I also use led lights throughout the car to lower the operating temps of the light and to reduce current draw to them.

You might consider switching from a main fuses to a main circuit breaker on the alternator cable etc, as it's easy to reset them. I also run a similar size ground cables from the alternator to my main ground. I do that with the starter too. Power flows equally through both + & -.

Regarding your alternators output at idle, try and find out at what rpm they are spinning it to get that many amps, and calculate what your pulley rpm will be with the pulleys you will be using. I suspect your pulleys wont be spinning as fast as how they were driving theirs, but who knows?
 

jrcr_15

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I found there is absolutely no need to run high amp power through the bulkhead connector. If you need to, use a separate bulkhead pass through that's rated for that amp load.

I run my alternator cable to the factory relay lug on one car with less electrical demand, then a second cable continues down to the starter. On my other car I use a distribution lug to send the power where needed. I've found that Marine Grade and high end stereo electrical components and wire are of much higher quality than I can find from auto parts sources. The fused distribution blocks are very cool from places like West Marine.

Use quality relays on every high amp draw circuit. keep all high amp draw feeds out of the bulkhead connector. I also use led lights throughout the car to lower the operating temps of the light and to reduce current draw to them.

You might consider switching from a main fuses to a main circuit breaker on the alternator cable etc, as it's easy to reset them. I also run a similar size ground cables from the alternator to my main ground. I do that with the starter too. Power flows equally through both + & -.

Regarding your alternators output at idle, try and find out at what rpm they are spinning it to get that many amps, and calculate what your pulley rpm will be with the pulleys you will be using. I suspect your pulleys wont be spinning as fast as how they were driving theirs, but who knows?
This is really helpful, thank you.
The vehicle you mentioned with a distribution lug. Do you have any photos you could share of your set up? Or even a schematic if you have one?
 

famous bob

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This is really helpful, thank you.
The vehicle you mentioned with a distribution lug. Do you have any photos you could share of your set up? Or even a schematic if you have one?

why not use the directions that will come w/ your kit , they will have a phone number for extra help
 
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