Here's some good info on lighting and voltage drop.
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>In many cases, the thin factory wires are inadequate even for the stock headlamp equipment. Headlamp bulb light output is severely compromised with decreased voltage. For example, normal engine-running voltage in a "12-volt" automotive electrical system is around 13.5 volts. At approximately this voltage, halogen headlamp bulbs achieve 100 percent of their design luminous output. When operating voltage drops to 95 percent (12.825v), headlamp bulbs produce only 83 percent of their rated light output. When voltage drops to 90 percent (12.15v), bulb output is only 67 percent of what it should be. And when voltage drops to 85 percent (11.475v), bulb output is a paltry 53 percent of normal! [Source: Hella KG Hueck AG, Germany].
http://www.danielsternlighting.com/t...ys/relays.html
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