Originally Posted by rosco11

I did a 69 lemans a while back. On this model, the power feed for the lights came directly from the regulator. No regulator, no lights. You need to find the 12v constant power wire going into the light switch and wire another 12 source to it after you cut out the regulator. On other GM models, that feed comes off of one of the pins on the horn relay. If yours goes to the horn relay, it will come from the regulator into the horn relay and again, you will need to feed that wire with 12v constant. If you still have the factory fuse panel, there are 2 bare spade pins in the center of the fuses. One is 12v constant for accessories like a power top the other is keyed on power for other add on accessories. You can plug your power feed for your lights in there and it will be fused.

The other wires coming into and out of the regulator you do not need. You can either de-wire them or just cut them out and terminate the ends. The only one you need is the main power going into the regulator tied back into your fuse panel constant power feed. The rest do something close to nothing. With a single wire alternator, which already has a regulator built in, you only need...1....wire going to the battery. 8awg minimum. If you still have the rest of the factory wiring, you already have power coming off of the starter motor wires feeding into your regulator, which now needs to be bypassed to your fuse panel.

You can also leave the regulator in if the wiring is sound to begin with. Not going to hurt anything. GM regulators are fairly reliable. Dodge regulators need to be cut out. They were problematic when they were new. In fact, if you are thinking of restoring a Dodge made before late eighties, consider an after market harness. Did a 86 ramcharger a while back. What a mess. Regulators put out anywhere between 13 to 16 volts, brand new. And i do not mean a range, i mean this one put out 13 volts, that one put out 16 volts and so forth. No rime or reason. just hit or miss. Lights were bright or dim depending on which regulator you had at any given moment. Turn signals worked or didn't, fast or slow, wipers were slow mo or good all depending on the stupid regulator. Lights on, wipers going AND you want to turn? ROFL, better hope you have the 15 or 16v one. The 13 volt was going to make you choose what you wanted based on priorities at the moment. Want a stereo with an amp? Better wire it directly to the battery and not via the factory harness.

About the factory "gen" light. On the LS alternator there is a 4 pin plug of which only one pin is used for the computer. The pin in the center right next to the CPU wire, brown i believe, can be wired directly to the "gen" warning light. That plug is hot when the alternator is putting out 12 volts or more and grounds when it is not. IE your "gen" light will go on when you turn the key on and go out when you start the motor. It will also go on when the alternator stops putting out voltage. That one wire is all you need to hook up to make it work. Just run a wire from that pin to the back of your instrument panel.

If you have not addressed the speedometer yet for the 68, this is what i did to mine. I took a factory tail section from a 700r4 with mechanical speedo and put it on the back of a 4L60, direct bolt on. Can use the factory speedo. You can then buy a converter that plugs into the trany and then into your factory cable and has an electronic 2 wire sensor for the LS cpu. I wanted to keep the factory gauges. And i did.

Originally Posted by alsalp

Thanks for the quick reply. What I have is a Carbureted 4.8 in my 68 Pontiac. So no LS ECU. Just 1968 harness. I have connected the "L" pin on the DR44G to the BLK/RD wire to #3 position on the old reg. The BLK/RD does indeed go through the horn relay. The GEN bulb was connected to the #4 Ext reg position and is now cut and looking for a home. The other side of the bulb goes to Pink/Blk to the GAUGE fuse and the other fuse is pink to "IGN" on the switch. My car is a wagon with a rear power window so i'm using the BAT spade. Are you saying I connect the Brown GEN wire (variable ground?) to a BAT12v or a Keyed 12v? I believe the brown wire went to ground through the old reg. Still learning.
thanks, Al
PS. I'm running a 700r4 with speedo cable so i'm good there thanks again.

Originally Posted by rosco11

The gen wire has power to one side of the bulb and a ground on the other that goes back to the regulator. The LS alternator brown wire, or center wire not going to cpu puts out 12 volts when running and grounds when it is not spinning. So your bulb gets ++ when running, ie, does not light up and +- when it is not spinning. Down side is it will not light up dimly when your battery starts going bad. Will only tell you if the alternator is putting out 12+ volts or not. For most people that is enough. Your amp meter gives you more information.
The other way to deal with it, if you are not using a ls style alternator is via a relay. Find a wire that is only hot when the engine is running, like a wire coming off your alternator for example, that does not go to the battery so there is no back feed from the battery, wire it to a relay activation pin and ground the through and through, one side to the body and the other to your gen light. Old style alternators have a trigger wire to tell the regulator when to turn on and off. Use that one after you cut out the regulator.
i can tell you how to set up your factory temp gauge to work with just about any temp sending unit too if you need it. I like to keep the factory dash.

Originally Posted by rosco11

Yep. LS1 and 2. 4 wire plug at top but normally only two wires coming out of it in the center. One is for the computer and if you do not have a computer, you do not need it connected. Other center pin on that plug is the one you can pin to your "gen" dummy light.

BTW look up "rally gauges" for your 68. There was an option for full instruments and a tack in the dash for 68/69. You may not have gauges now, but you can certainly get them. If you ordered a GTO you got the tach on the hood and a clock where the tack would have gone in the dash.

Originally Posted by rosco11

Get an ohm meter and find which one of the two center wires is grounded with the engine off. Then crank it and check that the same wire now has a charge. That is the wire to hook up to your GEN dummy light. Does not matter if it is 9 volts or 12. It will light up with any voltage.

Alternative is to buy a 5 pin relay and attach the charge wire that goes hot when the engine is running and run it to pin 86 or 85, doesn't matter. Ground the other one, 86 or 85 you didn't use. Ground pin 30. run wire from 87A to GEN light. Leave pin 87 unconnected. Engine not running, GEN light is grounded and on. Engine running, not grounded and not on.

No need to over think it. The GEN light is only looking for a ground to turn on. You only need to find a wire that is hot when alternator is spinning and grounded when it is not. Easy enough to use a OHM meter to check and it is one of the two center pins. Still confused, go buy a 5 pin relay and connect like above.

Originally Posted by rosco11

Doesn't matter. As long as it is close to 14 or higher, it will charge the battery. And as long as it has enough amperage, it will run the vehicle. Your alternator actually puts out a lot more voltage. It is the internal regulator that filters it down so you don't burn out the electronics on the car. Regulators were a big deal. And those old GM regulators actually did a really good job. But they are redundant now being most alternators all have built in regulators now.