Author Topic: 2 round to 4 square headlight conversion  (Read 6113 times)

Offline biggpoppa3

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2 round to 4 square headlight conversion
« on: June 30, 2011, 07:00:35 pm »
i got a 74 chevy half ton 4x4 about three months ago i converted it to the newer front end with four headlights, off a 87 blazer. i would like to know which lights a suppose to be what. i just plugged my existing wiring into the top two headlights and called that it for now. the only problem is the low beam is extremely dim like u cant even see the light on the road when sitting in the cab so ive been running on just the high beams. the top two have three prongs and the bottom have two prongs, so what i wanna know is how there suppost to wired up so that my low beams are brighter and hopefully high beams are brighter too

Offline Blazin

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Re: 2 round to 4 square headlight conversion
« Reply #1 on: June 30, 2011, 09:20:09 pm »
You need the wiring harness from the 87 .
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Offline Irish_Alley

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Re: 2 round to 4 square headlight conversion
« Reply #2 on: July 01, 2011, 09:28:38 am »
the top is low. like blaz said you need that wire setup off the 87 but it def sounds like a bad ground or connection problem.  i know on my 79 i had two wires crossed. low and ground and they worked but just where to dim to see anything i could drive with my high beams and it wouldn’t even bother on coming traffic
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Offline beastie_3

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Re: 2 round to 4 square headlight conversion
« Reply #3 on: July 01, 2011, 09:51:35 am »
ya would think top would be high beams and lower light, well, low beams.

Offline topp

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Re: 2 round to 4 square headlight conversion
« Reply #4 on: July 01, 2011, 11:21:55 am »
ya would think top would be high beams and lower light, well, low beams.

Actually, no you wouldn't think that.
Low beams are aimed more for the road, so for more visibility for the driver, they would be higher up to put more light further down the road.
High beams aim more straight ahead, so their placement under is less critical....
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Offline Edahall

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Re: 2 round to 4 square headlight conversion
« Reply #5 on: July 01, 2011, 02:11:43 pm »
Your truck seems like a good candidate for relaying the headlights.  It'll fix your problem and give you better light output than the stock setup.

This should get you in the right direction.
http://www.rowand.net/Shop/Tech/WiringHeadlightRelays.htm
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Offline beastie_3

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Re: 2 round to 4 square headlight conversion
« Reply #6 on: July 01, 2011, 04:15:06 pm »
Definitely do the relay kit, makes a world of difference.

Offline topp

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Re: 2 round to 4 square headlight conversion
« Reply #7 on: July 01, 2011, 11:20:40 pm »
Definitely do the relay kit, makes a world of difference.

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