Alternator upgrade

[Fer_]

Guys need help with a alternator upgrade. 70 challenger 340.has a low amp alternator. Running fitech, electric fans ,fuel pump.its a 2 field alt plus power and ground. Have a 100 amp I want to install but has only 1 field +power and ground.both external regulator.how do i wire the reg?2 wires from it.thanks for the help.

 

[moparleo]

A few things to note about the early Mopar charging system. Read before you put anymore load on the factory wiring.
Improved Wiring for older Mopars
Vintage Chrysler electrical repairs and updates
Vintage Chrysler electrical repairs and updates (part 2)
Catalog
Catalog
Denso Alternator Installation

 

[Fer_]

Thanks for the info. I have bypass the ammeter..have fan relays and head light relays..my fitech controler manages all the info from the motor.the only thing my cluster shows is speedometer and fuel gauge..nothing else is wired other than lights ,turn signal, no gauges. Have a separate oil pressure gauge. How can I wire the vr to the one field 100 amp alternator. Both are external vr.thanks

 

[moparleo]

So no other wiring is in the car ? Race car ? Why a 100 amp alternator ? You already have it and just want to use it ? What exactly do you already have ?

 

[Fer_]

Not a race car..I meant the only things wired in the cluster are the fuel gauge and the speedometer. My fitech controller has all new wiring to the rest of the components. I am running electric fans with relays, headlights with a relay kit,msd ignition, efi,..have a 60 amp alternator. At night with lights and when fans come on volts go down to below 12 v..when fans stop..starts charging again.alt has 2 fields..ext vr..got a 100 amp alternator..external vr but only has 1 field..just wanna know how I wire the regulator to it..or it wont work and i need to get a 1 wire with internal vr...thanks

 

[Fer_]

 

[moparleo]

Here is more info. This is a perfect example of what happens when you start to modify or "hot rod" any factory designed system. Electrical or not. Domino effect. One change always requires more other changes. Get a "system" .

 

[Fer_]

Get a system?
All I wanted was some info..I thought this is what this forum was for.Sorry to have bother you.
Moparleo...Dude you sound angry...I will figure it out thanks

 

[moparleo]

Never. Electrical always takes me a lot of reading and research. Have you read through the info that I have posted ? Your answer should be there. My point is that I want to know why things work . Some people just want the answer. A system means a compatible combination. Could be just 2 things. Not always complex.
Why isn't there anybody else posting on this ?

 

[fasjac]

Here’s some snap shots out of the EWD section that could help?? I run dual electric fans with a controller. All factory guages work perfectly. Alternator is 75amp. Factory voltage regulator. Disregard any highlights as I was working on different issues.

 

[Fer_]

Thank you very much.I will go thru it when I get home from work.really appreciated.
Maybe i can just hook up green wire from vr to 1 field alt and the blue one to a hot with ignition on

 

[MerlinsMopars]

Im pretty sure the single wire goes with the old style points setup. You might have to change the voltage reg to the old style. It might be best to sell that 1 and get a 2 wire. Mancini has a 100amp. Local parts stores may have 1 also. Probably easier than going thru and changing the harness wiring. Most will suggest not to use 1 that big but if your wiring is in good shape, you should be ok. I have 1 in my 68 and I have no issues. Think you run the blue from the alt to the points style regulator and out to the harness plug. Eliminate the green. Check the diagrams 1st tho.

 

[fasjac]

Thank you very much.I will go thru it when I get home from work.really appreciated.
Maybe i can just hook up green wire from vr to 1 field alt and the blue one to a hot with ignition on

Good luck Fer_ and let us know if all is good.

 

[Fer_]

Thanks I will

 

[Fer_]

Im pretty sure the single wire goes with the old style points setup. You might have to change the voltage reg to the old style. It might be best to sell that 1 and get a 2 wire. Mancini has a 100amp. Local parts stores may have 1 also. Probably easier than going thru and changing the harness wiring. Most will suggest not to use 1 that big but if your wiring is in good shape, you should be ok. I have 1 in my 68 and I have no issues. Think you run the blue from the alt to the points style regulator and out to the harness plug. Eliminate the green. Check the diagrams 1st tho.

Thanks a lot.You are right I think the best solution will be to get the alternator with the 2 fields.thanks a lot.i will look at Mancini

 

[moparleo]

There you go. Read on and get "the rest of the story".

 

[Fer_]

Ok so I found a 100 amp alternator from tuff stuff with 2 field..As soon as i get and install it i will keep you posted .
I was trying to use the one field one my friend gave me cause it was new and free.I just installed a gear vendors overdrive so was trying to save some money but.....oh well....thanks for your help and advice

 

[Dodgeboy]

I used the 90amp nismo alt from my dodge shadow and fab'd up a mounting bracket and installed in my 74. I by-passed the ameter and ran a second wire to the battery (from the alt) so the factory wire wouldn't burn up. Didn't have time to re-wire the car. Its been working fine for far, 4 years in. Off the top of my head I forget what major changes were made from 70-74 so i don't know how easy it will be for you. Mine was a simple swap, fab'ing a new alt bracket was the hardest but still pretty easy.

 

[Dodgeboy]

 

[fasjac]

And just for reference, a pic of my set up. Pretty simple. 75 amp, I just like the factory look. All good fellows!