Okok i have both alternators working as shown in previous posts and the second alternator and battery are completley isolated from the stock stuff.. (this problem was present before the second one was put it so that is not a factor)
Audi tested my alternator and said that is was fine. In the morning i get 14.4 and my volt meter is at the first line before the 16 (thats 14.4) as soon as i hit the lights it dropps to about 13 and as soon as the ac kicks on it drops below 12 and barley recovers once starting to move.. im lucky if i keep 12.. forget it if i have to put on the rear defroster! its never stalled on me before nor have i ever had a dead abttery (but if i did id just jump myself :)

any ideas?

Measure the voltage at the terminals. You may have a bad wire or connection. Look at the main power feed(s) and ground(s).

I trust your battery terminal connections are clean and tight. Car start good?

I do mean "at the battery" right on top of the terminals.