LED headlight upgrade, why the need for new wiring and relays???

[Nismobishi]

Hello,
I am looking at some stock looking 7" round headlight housings that take H4 LED bulbs and H4 connectors. I see everyone saying to make sure you add relays and Yada Yada. Why??? LED's draw much less current than conventional bulbs. Its not like a halogen or Xenon or something. This should be a plug and play replacement, should it not? 1965 Satellite is what I'm working on by the way.

https://www.amazon.com/gp/aw/d/B001OMEPEU/ref=ox_sc_saved_image_1?smid=ATVPDKIKX0DER&psc=1

https://www.amazon.com/gp/aw/d/B06XHD78DQ/ref=ox_sc_saved_image_2?smid=A16GA5NNY6O4GW&psc=1

https://www.amazon.com/gp/aw/d/B076JGTB7H/ref=ox_sc_saved_image_3?smid=A38J9K4U4VR7DQ&psc=1

 

[Lefty71]

Maybe worth a direct message to Crackedback and ask him.... many have raved about his system .

Crackedback wiring harness installed with pictures and video.

 

[mrmolding]

You know, I saw these a few months ago. Apparently no new wiring needed. Hmm...

Headlights - Holley

 

[Xp29h]

LED’s take less power for sure and work much better than the old stock lights! But they need their own grounds and their own special relays. They will not work with the old relays in the vehicle. Unless your wiring is in great shape, it wouldn’t hurt to replace with brand new harness. I know my wiring was awful and had been hacked up over the years. So, I completely rewired my car a few years ago and did led lights and bulbs in many places and found out about the grounds and special relays. My thought was fix it the first time! Heck, with all the wiring gone, I wasn’t going to be any closer!

I know you’re looking at headlights but I found a lot of stuff here that helped me out.. good luck!

LED Lighting For Everything | Super Bright LEDs

 

[mrmolding]

So there is a video off that page I linked. They mention nothing about grounding but maybe it gets it from the headlight buckets. Hmm...a little rich for my blood and I never drive it at night (so far).

 

[70ChargerRT]

You don’t need any special relays or grounding to run led head lights lol. The only reason you need to upgrade any relay under your dash, turn signal and flasher relay, is if you want to run led park lights and led turn signals and then that’s when you ground the relay. 5 3/4” led headlights fit my housings perfect on my Charger without any modifications. My 6k leds only pull I think 3.8 amps on low and 10.4 I think on high and that’s half of what they were stock. I’m making the complete swap over to LED lights on everything so I’ll eventually have to order another LED flasher. I already have one for my digi-tails.

 

[mrmolding]

You don’t need any special relays or grounding to run led head lights lol. The only reason you need to upgrade any relay under your dash, turn signal and flasher relay, is if you want to run led park lights and led turn signals and then that’s when you ground the relay. 5 3/4” led headlights fit my housings perfect on my Charger without any modifications. My 6k leds only pull I think 3.8 amps on low and 10.4 I think on high and that’s half of what they were stock. I’m making the complete swap over to LED lights on everything so I’ll eventually have to order another LED flasher. I already have one for my digi-tails.

Makes sense! My car had led bulbs in taillights and turn signals when I got it but it was flaky. Everything worked after I put in a new led flasher and grounded the flasher. I had to switch flasher polarity as well.

 

[70ChargerRT]

Makes sense! My car had led bulbs in taillights and turn signals when I got it but it was flaky. Everything worked after I put in a new led flasher and grounded the flasher. I had to switch flasher polarity as well.

Im thinking the digi-tail relay has reverse polarity built in them.

 

[Crackedback]

Any time you can take electrical loads off the factory harness, that's a good thing.

 

[Nismobishi]

LED’s take less power for sure and work much better than the old stock lights! But they need their own grounds and their own special relays. They will not work with the old relays in the vehicle. Unless your wiring is in great shape, it wouldn’t hurt to replace with brand new harness. I know my wiring was awful and had been hacked up over the years. So, I completely rewired my car a few years ago and did led lights and bulbs in many places and found out about the grounds and special relays. My thought was fix it the first time! Heck, with all the wiring gone, I wasn’t going to be any closer!

I know you’re looking at headlights but I found a lot of stuff here that helped me out.. good luck!

LED Lighting For Everything | Super Bright LEDs

I can see needing good grounds, As all electrical loads need. Special relays though, All relays are the same, except for how much power they can handle. They are basically an on and off switch operated by a 12v signal sent to them. Maybe they need to be replaced if they are old and failing but there is no special relay that would be needed just for a headlight upgrade as long as the stock relays are in good shape.

 

[Nismobishi]

Im thinking the digi-tail relay has reverse polarity built in them.

You can make any relay control a ground circuit or a power circuit. It is like an on/off switch for what ever circuit that you hook up to it.

 

[70ChargerRT]

You can make any relay control a ground circuit or a power circuit. It is like an on/off switch for what ever circuit that you hook up to it.

Yeah I know that, kind of lol. It’s kind of like an electrical fan relay. When you’re running carbs you control the fans with a power circuit but when you’re running efi you have to control it with a ground circuit but I’m definitely no electrical genius, far from it but I’m kind of loss in what your trying to say unless you’re saying I can take a Bosch type relay and wire it myself for the LED flashers to get the reverse polarity and then ground it? I need to buy new relays anyways so I’ll just buy a plug n play relay and ground it with this type relay. All new wiring harness plus I overkilled the grounding which is good for everything, especially my Sniper.

 

[72sunroof]

Hello,
I am looking at some stock looking 7" round headlight housings that take H4 LED bulbs and H4 connectors. I see everyone saying to make sure you add relays and Yada Yada. Why??? LED's draw much less current than conventional bulbs. Its not like a halogen or Xenon or something. This should be a plug and play replacement, should it not? 1965 Satellite is what I'm working on by the way.

https://www.amazon.com/gp/aw/d/B001OMEPEU/ref=ox_sc_saved_image_1?smid=ATVPDKIKX0DER&psc=1

https://www.amazon.com/gp/aw/d/B06XHD78DQ/ref=ox_sc_saved_image_2?smid=A16GA5NNY6O4GW&psc=1

https://www.amazon.com/gp/aw/d/B076JGTB7H/ref=ox_sc_saved_image_3?smid=A38J9K4U4VR7DQ&psc=1

You don't need a relay for LEDs they draw less than stock bulbs, you do need a resistor if you have hidden headlights. The h4 bulbs plug right into your existing harness. Your selections look good.
I have had mine for 4 years 0 issues. H4 housings with an Led h4 bulb

 

[Nismobishi]

You don't need a relay for LEDs they draw less than stock bulbs, you do need a resistor if you have hidden headlights. The h4 bulbs plug right into your existing harness. Your selections look good.
I have had mine for 4 years 0 issues. H4 housings with an Led h4 bulb

Thank you for the input!

 

[Sinitro]

Last year I installed (4) Holley retrobrites in my 70 RR, no relays are required. I did fabricate a Y connector so that I could connect (2) lites for each side in parallel, so I have (4) low or high. The Holleys' are great, nice wide dispersion but not overpowering to oncoming traffic. A nice touch is no cutting of the bucket is needed. Shop around some places are discounting these.

Just my $0.02...

 

[mrmolding]

So I wanted to mention that I went to the "LED" side and got what I mentioned in post #5 and Sinitiro in #15, the Holley Retrobrights. It's been so hot in the desert above LA that I've been doing a lot of night driving. It's really frustrating when you are in a swarm of LED headlights and you worry that someone is going to hit your baby with a vintage year set of Wagner 4000s you found in an old box.

There was no way I was going to pay full price for the Retrobrights so I waited. I almost got an octane lighting set, but I found an eBay seller who has open box Holley's and I offered 65 (75 maybe?) each. So I got a total of four, two low and two high beam, and he accepted. Anyway for 300 for a set, I was willing to give it a shot and the seller takes returns. I got the modern white versions from the seller.

I put them in last night and the picture above in Sinitro's post is spot on. I think for the first time that I've recently driven at night, you feel seen by the other drivers. A brand new Sublime Challenger Swinger model came up to me at a light and of course we were drooling over each other's cars.

Anyway, no additional harness, went right in, and they look pretty close to stock. They do have the Holley brand and are a little flat looking, but are definitely a huge improvement. It's like it draws out the large white flat field of view as in modern cars, but looking about as stock as you can get. Very pleased, just need to find a decent wall 25 feet away so I can aim them a little better. If anyone has a magic formula other than the 25 foot and aim about 2 inches below the center of your headlight on the wall, I'm all ears. Just don't have a deep enough garage and my driveway is not level.

Anyway, again, I wanted to share that since I waited out the h1 harnesses, relays, etc. and found something that went in with no mods, and a "fairly" decent price, I'm pretty pleased! We shall see how long they last!

 

[72RoadrunnerGTX]

Do LEDs require relays? Any headlamp system will benefit from the elimination of the voltage drop in the original headlamp circuit. The resistance at every connection and switch between the alternator output stud and the lamps contributes to the total voltage drop at the lamps. Yes, LEDs use less current than any incandescent bulb system but still does draw current, will still have some voltage drop that can easily be reduced to almost nothing with relays.

Relays are cheap, pre-made kits are available and will suit some well but are not always necessary, easy enough to wire in a couple of relays.

 

[440 PHIXX]

Makes sense! My car had led bulbs in taillights and turn signals when I got it but it was flaky. Everything worked after I put in a new led flasher and grounded the flasher. I had to switch flasher polarity as well.

LED’s being diodes only flow current in one direction. You won’t hurt them flowing the wrong way, they just won’t light.

 

[mrmolding]

LED’s being diodes only flow current in one direction. You won’t hurt them flowing the wrong way, they just won’t light.

They came with a reverse polarity mini harness for low beams. The brights can be flipped over with the plug. I figured that out since at first the brights did not work. Just back from a 1.5 hour cruise. Great to see the road so well!

 

[Mopar Hunter]

So I wanted to mention that I went to the "LED" side and got what I mentioned in post #5 and Sinitiro in #15, the Holley Retrobrights. It's been so hot in the desert above LA that I've been doing a lot of night driving. It's really frustrating when you are in a swarm of LED headlights and you worry that someone is going to hit your baby with a vintage year set of Wagner 4000s you found in an old box.

There was no way I was going to pay full price for the Retrobrights so I waited. I almost got an octane lighting set, but I found an eBay seller who has open box Holley's and I offered 65 (75 maybe?) each. So I got a total of four, two low and two high beam, and he accepted. Anyway for 300 for a set, I was willing to give it a shot and the seller takes returns. I got the modern white versions from the seller.

I put them in last night and the picture above in Sinitro's post is spot on. I think for the first time that I've recently driven at night, you feel seen by the other drivers. A brand new Sublime Challenger Swinger model came up to me at a light and of course we were drooling over each other's cars.

Anyway, no additional harness, went right in, and they look pretty close to stock. They do have the Holley brand and are a little flat looking, but are definitely a huge improvement. It's like it draws out the large white flat field of view as in modern cars, but looking about as stock as you can get. Very pleased, just need to find a decent wall 25 feet away so I can aim them a little better. If anyone has a magic formula other than the 25 foot and aim about 2 inches below the center of your headlight on the wall, I'm all ears. Just don't have a deep enough garage and my driveway is not level.

Anyway, again, I wanted to share that since I waited out the h1 harnesses, relays, etc. and found something that went in with no mods, and a "fairly" decent price, I'm pretty pleased! We shall see how long they last!

Jegs will match eBay sellers pricing, they will have the new Retrobrights drop shipped to your home. That way you don’t buy someone’s return or defects that will short when you hit a bump in the road.