Okay, so I tried the connection from the ignition part to the regulator to the pos of the battery and had gotten no change. All it did was go back down to 12.3 volts, connect the plug again and it jumps back up to 14.9-15.2. .
when the fans come on it goes down to like 13.1 and when the lights are on (with the fans running) it goes down further 12.5...also, I had tried this with a new regulator I had just bought today.
It may be possible that you have two problems. Voltage DROPPING under load is an indication of either an alternator that is too small (amperage) or is has one or more bad diodes/ windings and is not putting out it's rated amperage.
OR you may have a voltage drop IN THE MAIN CHARGE LEAD between the alternator and the battery
I believe you said you bypassed the ammeter? Just how did you do this, exactly and what size wire did you use?
