SMD headlight question

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Jack Kwiat
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SMD headlight question

#1 Post by Jack Kwiat »

I was wondering if it would be feasible to use SMD headlight bulb/ units while also using headlight relays? I'm currently using H4 bulbs in European headlight assemblies. Would I have to disconnect the relays and go back to straight wiring?
These are what I had in mind. https://www.amazon.com/gp/product/B07GN ... _550134450
Thank you!
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Dave Lagerstrom
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Re: SMD headlight question

#2 Post by Dave Lagerstrom »

I can't comment on the bulb you are considering. If you have relays for your headlights and they are working, switching to a LED bulb will not be a problem. You can keep the relays in place.

These bulbs will use < 2 amps each. Actually, 1.667 @ 6 volts. Depending on the state of you wiring, you may not need the relays any more, but they certainly won't hurt anything.
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David Jones
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Re: SMD headlight question

#3 Post by David Jones »

Jack. Take a little time and do a search on smd lights. There are many comments. I doubt the bulbs you referenced will have a very good beam pattern.
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Jack Kwiat
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Re: SMD headlight question

#4 Post by Jack Kwiat »

Thank you for your input, Dave and David. I will try to research them a little more.
The headlights are a bit brighter using the H4's and dual relays. Perhaps I'm wanting too much out of my 6-volt system..?
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Re: SMD headlight question

#5 Post by David Jones »

here are my SMD LED's Jack.
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Paul Ahnell
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Re: SMD headlight question

#6 Post by Paul Ahnell »

David: I'm impressed by the pattern of your SMDs lighting up that tree-lined lane. I live in a rural area with roads much like that with critters lurking in the woods. I have Jeffery's Classico Wheels system which, while bright, have never had a concentrated pattern like that. Mine is spread out and up rather than directed straight ahead. What system are you using?
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Jack Kwiat
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Re: SMD headlight question

#7 Post by Jack Kwiat »

David, I'm also impressed with how well your headlight system throws a nice beam. What system are you using?
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Jay Broemmel
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Re: SMD headlight question

#8 Post by Jay Broemmel »

I have 6v H4 with relay set up and switched to non-Jeffrey LED “bulbs”. No problems with relays still in place. J

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David Jones
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Re: SMD headlight question

#9 Post by David Jones »

Here is a link to an earlier thread on LED and SMD headlight conversion.
viewtopic.php?f=1&t=50648&hilit=led+headlights
As I stated the LED's I chose were not a perfect fit due to them being really too close to the rear of the headlight housing so a set with maybe a 1/4" shorter base section would be ideal. Nevertheless the headlights are an incredible improvement over the 6 volt QH and the reduction in current draw is one of the main reasons for doing the conversion.I tried a few bulbs before settling on the ones I used and rejected many mainly because they had no light penetration and were very badly focussed. I would never use one with multiple SMD's as shown in Jacks amazon link because the multiple SMD's cannot be properly focused. The attached picture shows one I used that was very bright but again no penetration and the one I ended up using which has the SMD positioned so that the reflector actually has a distinct cut off pattern on low beam whilst having excellent focusing on high beam. The one with the round SMD is the rejected one.
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Mark Roth
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Re: SMD headlight question

#10 Post by Mark Roth »

Check out this topic.
viewtopic.php?t=37564
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Jack Kwiat
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Re: SMD headlight question

#11 Post by Jack Kwiat »

David,
Thank you for enlightening me further on the subject...you can never have too much information.
So it's the upper unit that you used, and where did you acquire it?

Mark,
Thank you for the link to an earlier thread on the subject. Very interesting indeed.

Jay,
Thank you for your input.
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Re: SMD headlight question

#12 Post by David Jones »

Jack, I bought them off Amazon but please note that I still have a 6 volt system on my car so I had to use a 2 x 6 to 12 volt converters to drive the lights. Still under $100 total cost.
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Dan Kalinski
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Re: SMD headlight question

#13 Post by Dan Kalinski »

David, that is impressive lighting to say the least and for under a hundred bucks, wonderful stuff.

Would you please let us know the converters you used and the “tips & tricks” used to wire this system? I’d love to install this system in my ‘59 and the ‘55.

Thank you for all that you contribute here.

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Re: SMD headlight question

#14 Post by David Jones »

Dan, this earlier topic covers the lights and power supplies. If you want me to be more specific as to the wiring PM me and I can give you the details and pictures of how I did iy in my T2 and in a T6. In essence all I did was take the input to the fuses for the high and low beams and fed it into a 6 to 12 volt converter then connected the 12 volt output to the fuses and also changed the high beam indicator bulb to a 12 volt one. If you look at the circuit for the headlights you will see that the 12 volts does not interact with anything else.
viewtopic.php?f=1&t=37564

These are the 6 to 12 volt converters I used. There are cheaper 3 amp ones but I like to have the extra capacity just in case.https://smile.amazon.com/DROK-Voltage-R ... 39&sr=8-18
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Re: SMD headlight question

#15 Post by Dan Kalinski »

David Jones wrote: Fri Nov 13, 2020 11:30 pm Dan, this earlier topic covers the lights and power supplies. If you want me to be more specific as to the wiring PM me and I can give you the details and pictures of how I did iy in my T2 and in a T6. In essence all I did was take the input to the fuses for the high and low beams and fed it into a 6 to 12 volt converter then connected the 12 volt output to the fuses and also changed the high beam indicator bulb to a 12 volt one. If you look at the circuit for the headlights you will see that the 12 volts does not interact with anything else.
viewtopic.php?f=1&t=37564

These are the 6 to 12 volt converters I used. There are cheaper 3 amp ones but I like to have the extra capacity just in case.https://smile.amazon.com/DROK-Voltage-R ... 39&sr=8-18
Wonderful! Thank you, Sir!

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