Alternator Upgrade Checklist.

[Wrencher]

Hey guys,

Recently I have taken on my 66 Dart /6 head on with the wiring changes that these cars require after many years in service. This included;

Ammeter bypass - I used the MAD method, which wires the ammeter wires (and the welded splice) in parallel, making the starter solenoid the new main buss. I replaced the starter solenoid as well.

Alternator Charging wire - Replaced the old wire with an 8ga wire, running to the solenoid, not through the bulkhead anymore. Wire is currently unprotected but I have 12ga fusable links on order

Bulkhead connectors - Cleaned these terminals as best as possible with a wire brush and electronics cleaner, and put Dielectric grease on the terminals to help keep corrosion out.

Instrument Cluster Voltage "limiter" - Replaced the old mechanical voltage limiter for the cluster with a solid state 7805 voltage regulator.


Alternator output was very poor even before starting these changes, and has only marginally improved since them. At 2k rpm, the alternator WAS pushing 7-9 amps, and now it holds about 13amps. I still have the old mechanical voltage regulator as well, which ive checked the ground and the terminals on.

So what I've just done is ordered a newer Nippendenso 120a Alternator from Rock auto ($45 seemed like a steal and I couldnt pass it up). It is for a 1990 Ramcharger. I also ordered the solid state voltage regulator & pigtail.

My plan is to install the voltage regulator as shown here

My only modification here will be a relay wired into the ignition switch wire. Im doing this to lift the load off the factory wire. Im doing this wherever possible, the headlights are next in line.

As you probably well know, the newer generation alternators are capable of much higher output at low rpm's, doing away with voltage dropping off or even fluctuating on extended idle. The round back and squareback alternators just never could achieve this, so I feel like its well worth the investment.


So theres my checklist, is there something else that needs attention that I'm overlooking? Please let me know. Thanks :coffee2:

 

[67Dart273]

Since you have gone to a relay for the ignition buss and plan to for headlights, consider getting an underhood relay box.

Bussman makes some nice ones that you can configure yourself, or you can rob one out of a junker. I recently picked one up out of a Jeep Cherokee, but the one I'm using in my 67 is out of a Voyager van. It mounts nicely on the fender apron to the rear of the battery:

This box required some rewiring, but easily done, and has fuses which you can use for various loads. I have relays for ignition, pump, headlights, and security, and more than one unused for later

 

[BillGrissom]

I did as 67Dart273, using a 95 Jeep relay box (search for my post). If your lights dim while idling, that is sympomatic of voltage drops thru the bulkhead and harnesses. They should be bright from just the battery alone. The alternator's purpose is to recharge the battery.

Insure that the new alternator doesn't have a built-in Vreg, since many do. If just a simple 2-wire field, you could get an electronic Vreg for your 66 Dart ($11 rockauto) that hooks directly to your existing wiring. At the alternator, just wire one terminal to ground (case of alternator). Not sure, but I think you will need a different adjustment arm for the new alternator. It needs more curve to hook up to the adjustment bolt.

 

[KitCarlson]

Will the 120A unit need two belts? At full load and losses considered, the belt load may approach 4 HP.

 

[RedFish]

You can decrease the load and possibly extend the life of your ignition switch with a realy outside the friewall as shown.
The downside of robbing a relay enclosure from some other vehicle is labelled wrong, wire colors wrong. You could end up rebuilding the thing. Relays dont really need to be all in one place or in an fancy enclosure anyway.
My headlight and horn relays are all on the right fender apron with fused power supply off the alternator stud.

 

[chryslerfat]

Always nice to have a diagram like that to start with.