Voltage Regulator Bypass

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vynn3

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Two questions: I'm in the process of upgrading the standard alternator in my 1967 Dart to a 60amp Denso unit. (I'm also making all of the recommended wiring upgrades/bypass).

The Denso alternator is internally regulated, so the factory voltage regulator should be bypassed. My question is, does that mean that I just connect the blue and green wires that currently go into/out of the factory regulator together?

My second question is, can the current green wire to the factory alternator be used as the switched 12v source for the Denso unit? (I understand the the "sense" wire will be connected to the starter relay along with the larger charge wire.)
 
Sounds like you are wanting to use the old green VR wire for "excitation" on the Denso. I'd say yes, hook the green to the blue, and the green to wherever it goes on the Denso

Resist the temptation to incorporate the "sense" and the charge wire into one. This "can be" a problem with "one wire" setups, as high current in the charge wire causes voltage drop, and causes the sense to read wrong.

Frankly, I'd run the sense wire (fused) DIRECT to the battery, or as absolutely close as you can get
 
Two questions:

does that mean that I just connect the blue and green wires that currently go into/out of the factory regulator together?

My second question is, can the current green wire to the factory alternator be used as the switched 12v source for the Denso unit? (I understand the the "sense" wire will be connected to the starter relay along with the larger charge wire.)

You guys are correct. I did this to my '67 Belvedere using a parts-store alternator for a 1991 Toyota 4Runner 4-cylinder (they have a v-belt pulley).

I even spliced the factory wiring into a Toyota repair connector very much like the following:

ALTERNATOR REPAIR PLUG HARNESS 3 WIRE PIN CONNECTOR Fits TOYOTA Camry Celica MR2 | eBay

I'm assuming one of the recommendations you have followed is bypassing the factory dash ammeter. I did that to my car also, and used the 12g black wire from the factory alternator charging lug as the sense wire.

It sounds like you're going in the right direction, & I'm sure it'll work nice when you're done.
 
Yep, I'm using the same Denso pigtail as you did.

I'll also be bypassing the factory ammeter by connecting the two leads, and adding an aftermarket voltmeter.
 
I am using a denso 60A alternator. It has the standard power output lug on it, then uses a 2 wire T shaped plug. The pin out on it is labelled I for ignition and L for indicator light. I am going to tie the blue and green wires together to eliminate the points regulator. I made an indicator light for the ammeter gage.
 
Thanks for all the confirmation/tips. I’ll connect the “sense” (fused) to the battery.

I was also considering utilizing the indicator light output. I can’t think of a good reason not to...
 
Heres what I did on mine. I used a 12v red LED light and drilled a #50 drill hole on the discharge side of the ammeter. I also converted the ammeter to volts. The indicator light gets its power via ignition switch. The contactor for it is in the alternator. When you rotate the key on, the contactor for the light closes to ground to illuminate it. On startup when the alternator starts working the indicator light contactor opens and the light goes out. If the alternator goes offline, the indicator light closes to ground and the light goes on. I used a small enough hole, and a red 12V led that's JB welded in. You can see it's getting its power off the volt gage 12V feed

downloadfile-3.jpg


Screenshot_2016-08-04-17-51-51.jpg
 
Any idea what size fuse to use for the "sense" wire to the battery?
 
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