alt gauge drops low

[moparx5]

 ok now that all my lights and blinkers work and today was the maiden voyage shake down ride
the alt gauge drops way down when i run the head lights
alt is new but i wouldn't rule out a defective
have never tested factory gauge nor do i know how
any feed back
thanks

[dodj]

The ammeter is a 'full flow' ammeter so reacts quite a bit when high current devices are turned on. Common for it to show discharge at idle. Are you still on the charge side when cruising with the lights on?
Unless you are an originality guy, look into the headlight relay mod, alternator bypass mod and voltmeter mod.

[moparx5]

 the car is pretty much stock original , drops down under power, only mod was a msd ready to run distributor , had to bypass the ballast resistor to have that work properly

[Mr Lee]

Recently, my volt gauge (I swapped out the ammeter for a volt gauge) was reading low while driving and wore out my battery.  Changed the alternator. Nothin.  Changed the voltage regulator.  Fixed.  Not sure if the headlights should be making yours run low, but changing the volt reg is an easy and relatively cheap place to start.