Help with 5 3/4" H4 headlights

[bkskylark]

Hello and good afternoon

I have a 1972 Buick Skylark 4 door 350 and I would like to upgrade the sealed headlights to the H4 headlights.

My only problem is that the cup that the old headlights sits in had to be cut somewhat to fit the lights in.

There is also the springs that hold the cup in place.

Should I change all the wiring for the headlights to new wiring or just cut and adapt the wiring?

52963 These are the lights that Im using, but I hate that spring that holds the cup in place.

Please help me out.

[chops101]

Since your new lamps draw more current than OEM, I would suggest adding power relays (2) to your circuit. This way you supply the absolute max power to your lights without all the voltage drop routing all around in yor dash, and also the OEM wiring could be under rated for the current demand of the new lights.

[bkskylark]

Thanks for the help.
Where do I get the power relays?

[rossmacd]

You can get relays at just about any auto parts store. When I did my h4 upgrade, I didn't have the time to do the wiring, so I got an h4 conversion harness from painless wiring. A little pricey, but it's worked perfectly for all these years and greatly simplified my install.

[bkskylark]

Ive done that but the wiring for the existing headlights are the original wiring. Should I change them to new wiring?

[First Bird]

"I've done that". What did you do?

What rossmacd means by harness is pre-made wiring for the relays to run your hot new h4's. you have to understand and use relays with these headlights because they draw more current than OE. If you run your original wiring the lights won't be as bright as they could be and you might burn up your wiring.

[Twentyover]

Use the existing wiring harness as a trigger for switching the relays.Run a fused power from the batter positive for powering the relays/lights.

If you're reaching the limit of your electrical confidence,
http://www.rallylights.com/SMS_Custom_Wiring_Harnesses.aspx

[CreepinDeth]

First off,
H4 is a halogen bulb size (like 9005, 9006, etc), not a bulb type.
HID is a bulb TYPE that's not Halogen. It's High Intensity Discharge.
HID system's also have a projector glass housing that projects the beam properly.

The picture you posted looks to be an HID headlights system with a set of ballasts and ignitors.
Don't confused the two. Just trying to help you understand the difference. :)

Throwing a relay in with a thick gauge wire allows the headlights to get less voltage drop and
more juice then you get through long runs of thin wire and 40 year old connectors with corrosion.

I did the $30 H4 conversion on my 1970 442 with relays for regular HL's and Brights, electric fans, etc.
All were mounted to a 1" aluminum barstock I painted, bent and used as a mounting bracket.

Read.
http://www.madelectrical.com/electricaltech/brighter-headlights.shtml

Auto relays are at any Radio Shack for $5 a pop or auto parts stores.
Plenty of simple wiring how to's online via Google.