OK so I'm getting old, and having a hard time driving at night. So I found this and tripled the output of my head lights of all my vehicles.

A little background, the stock lighting on most older cars with sealed beam lamps just plain sucks, and newer cars really aren't much better. Sylvania made a big leap with their Silver Star and Silver Star Plus line of replacements but, for me it still wasn't enough. I wanted to out shine the high end imports and their HID systems, and I wanted to do it cheap. I have been running this upgrade on both XJ's for over 3 years and the LHS for 6 months and the only problem I've found is it tends to burn out cheap bulbs pretty fast (as fast as 6 months), so use better bulbs.
This is a simple upgrade and can be done in a few hours and for less than 25 bucks, unless you get new bulbs.

The link is for older sealed beam or H-4 style lamps.
(Link removed)


NOTE ON ABOVE DRAWING: Ther e should be a 20amp fuse between relay terminal 30 and battery positive (+)


Newer cars with 9*** style bulbs can still be upgraded but you need an old bulb to make an adapter plug.

Making the adapter plug: take old bulb and wrap the glass part in a rag, break the glass with plyers (it makes a really loud pop when you do this). Break off all of the glass. Inside the bulb you will find 2 or 3 solid wires that attach to the filiment, remove the filiment, separate these wires, crimp a butt connector to each one, making sure none of the wires are touching fill the cavity in the base with silicone and let it set up for a few hours. Follow the instructions in the
above link.

 

Alright, so I have a question, and it might just be because I'm on no sleep right now, but how does adding a relay make the lights brighter? What causes it? I probably sound like a smart *** and I don't mean to, I'm serious, how does this work to our advantage. Like I said, I would probably be able to figure this out if I wasn't so tired, but I can't really think right now, and besides, maybe someone else here wants to know the science behind how it works. Thanks in advance for not hating me for asking a dumb question

 

SIMPLE ANSWER: Resistance, or lack there of. Your stock headlamp wiring uses 20 to 30 feet of light gauge wire, as light as 20ga, to power your headlamps, throw in the switch, fuses and a power distribution center and you get lots of resistance.

With this setup the wires are much heavier 10 or 12ga and you eliminate the power going through the light switch. Lets review a little expierment I did with my 90 Jeep. I unplugged one of my head lights, and hooked a volt meeter to the low beam terminal, started the Jeep and turned the lights on. I got a reading of 11.6VDC at the plug. I then tested the input to the HL switch and got a reading of 11.9VDC. The battery/alternator was producing 13.8VDC. Over the full run of wiring I lost 2.2VDC to resistance.
Same Jeep with the relay upgrade and 10GA wire. HL switch 11.9VDC (SAME), 13.8VDC Battery (SAME), 13.6VDC at the low beam connection, a loss of only .2VDC.

In a relayed headlamp setup the switch only closes a relay, the power for your head lamps actually comes directly from the battery and with the heavier gauge wires gets there with less resistance.

 

ok, that makes a lot of sense, more so now that I've had a little sleep. Cool, thanks!