Originally Posted by JeffB
There is something that a lot of folks miss and that is the use of relays when doing a rewire this explains it well: Custom Cars Classic Hotrods Streetrods-Watsons StreetWorks
Here in the archives of hotrodders.com are many articles by the late Doc. Vette who helped me out a while back.Two places you never want to run without a relay is an electric fuel pump and an electric fan(these draw a large amp load),a common complaint with older cars is dim headlights even though they have been halogen upgraded.I added the relays as per the link and WOW! major lighting improvement!
I had put halogen bulbs in my '64 Corvette years ago and while it helped, it wasn't all that impressive.
About a month ago, I did the headlight relay conversion. I run a 1-wire alternator, so I hid the new headlight relays in the old voltage regulator casing. Note that in GM fashion, this taps off the horn relay that receives its current directly from the alternator.
Using the photometer in my Nikon, I estimate that this conversion made the low beams 100% brighter and the high beams 66% brighter. Others report similar increases. This also takes a load off of your dash lights and they too get brighter.