Any reason why my 03 factory headlights didn't dim at all but my 08 swapped lights dim even when voltage reads 13 or higher when playing my stereo at full tilt? Open to anything!

 

Not enough info...how many watts are you pushing and what kind of electrical setup do u have

 

I have a grounding kit and around 1800 watts. Could a capacitor solve my problem? I am also rolling with the stock battery.

 

The voltage on the gauge isn't displaying what's going on at the input to your HID lights. Sounds like the new HID lights are more sensitive than the old filament ones. I'd connect a volt meter up to the HID transformer input and see what happens when you turn on the stereo system.

A large cap would help a bit. If you're battery is 6 years old that needs to be changed out too IMHO.

 

I know what you mean by the voltage dropping. I have been through probably 10 sets of HID and never once seen flicker or dim. I believe the battery is newer. I would like to replace with a kinetic 1400 which ever one will fit.