I have an 86 Z28 with an 84 305 motor. I have a good alternator but for some reason the voltage reg. isn't kicking in. What TELLS the voltage regulator to start charging? I replaced the batt, alt, cables, and choke relay. All my fuses are out of the car.

 

If the voltage regulator isn't kicking in, the voltage regulator is the problem. It tells itself when to kick on. To test, while the engine is running, take a small diameter screwdriver, touch it to the back of the regulator and rock the screwdriver until it touches the case of the alternator. (Older style alternators had a "D" shaped hole in the case, newer styles had rectangle openings). Touching the regulator to the case grounds it out and makes it go to "full on" mode. If you have a volt meter hooked up to the hot lead on the alternator, you'll be able to see the meter peg high. You should also be able to hear the alternator "whine" from the heavy load. You only need to ground it out momentarily, and you won't get hurt. If you are getting a low voltage reading while the alternator is running on it's own and it pegs when you ground it out, then the regulator is definitely bad. You have the option of replacing the whole alternator, or you can buy just the regulator. You need to dismantle the alternator to replace the regulator, so if you're not up to that task, an alternator replacement is your only other option. I'm doing a regulator replacement right now on a Delco alternator on a Jeep. It's not all that difficult, but I've been inside an alternator a few times before.
EDIT: in case you're wondering what the regulator looks like, take a look through the back of the alternator case, near the regulator plug. The back of the regulator is a shiny metal. It's mounted inside the alternator with insulators, which is why you need a screwdriver to ground it out for the test.

 

Ok dont laugh..... When i removed the original alt. the white cilp broke so Im working with two seperate wires now. Well i put the red on the bottom and the brown on the top LOL backwards. So I decided to switch them tonight and the car is running perfectly at 14v. I have been driving it all night with no problems!!!!

 

I laughed anyway!