LED replacement bulbs

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cudamark

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Hi all, I've done a search here and can't seem to find the answer I'm looking for. I have a '66 Barracuda and want to install some LED bulbs for the backup lights and lower taillights. On a side note, even the factory parts book and owners manual doesn't show which bulb is used for the lower taillights! I'm assuming it's the same 1073 as the backup lights, but, I may be totally wrong! Anyway, I see a 7506 LED bulb is supposed to be the replacement for the backup lights. The potential problem I see is the length of the bulb. This model has historic problems with melting the lenses on the taillights because of how close the bulb is to the plastic lenses. I'd like to use a short bulb (like a license plate bulb) but, I don't see one listed that is that short. I guess I will try the 7506's, but, a couple of questions. What sort of heat does this bulb produce? Hopefully less than the incandescent one it replaces. One version is slightly longer than the 1073, so, that is a concern. Also, Sylvania says it's not street legal....what the heck is the deal there? Just hasn't been fully tested yet to get the DOT approval? The specs on the bulbs don't compare apples to apples in some cases. Some bulb use watts, some use lumens, some also list color temp in Kelvin. That makes it hard to compare when it comes to light output and heat generated. I'm basically trying to get a brighter light without adding heat to the lens. Otherwise, I'll just use the stock incandescent bulbs. Any suggestions?
 
LED bulb runs on about 0.5 to 0.75v

To run in a car it either hasn't to have some sort of voltage regulator or resister to lower the voltage. Or the 0.5v bulbs have to be wired in series internally to add up to about 12V so 24 LEDs .

All that being said...

If it uses a voltage regulator it will generate some heat but much less than an incondescent bulb

If it uses a resister it will generate as much heat as an incondescent AND draw the same current as the incondescent. Totally defeats the purpose.

If it has about 24 internal LEDs it would run about as hot as a voltage regulated version.
 
1073 is backup light =1156WLED (Phillips)
1034A is amber front turn signal / parking light =1157ALED (Phillips)
1034 is rear brake light / parking light = 1157RLED (Phillips)

This is per Rock auto.
The FSM wiring diagram shows the extra bulbs for Barracuda only. Single power in and housing ground, like back up light.

Screenshot_20220202-211623~2.png
 
The incandescent 1157's will melt lenses in a '66 Barracuda. It sounds like the LED versions might be cool enough if they're not too long.
 
What do the lower lamps do you mentioned? Are the actually tail? If so you don't want the same bright lamps as the backup lamps, you want a dimmer less wattage bulb. I'm not familiar with the old girls
 
Yes, on the Barracuda, there are two taillights on each side...an upper (with the turn signal) and lower all by itself. I don't mind a nice bright taillight.
 
I converted everything to led 5 or 6 years ago, I used the philips xtreme vision led series for as much as I could and everything is working great. You need to get an led bulb that is the same color as the lense it goes behind for it to light up evenly.
 
You have to look at the LED lamp and figure out where the diode’s are facing. Incandescent lamps radiate light almost equally in all directions. The shape of the reflector or housing and the grooves on the lens direct the light in the direction you want. LED diodes really only project light out the end. Some "replacements" have the correct base, but the LEDs all face straight out the end, or 90° from the base, or some that have small diodes on a cylindrical "drum" facing in all directions, (would SEEM to be the most appropriate). Not saying don’t change to LED, just be careful to make sure you get the "finished" light output you are seeking.
While bright tail lights are nice, consider that it might be just as bright as your brake lights, so
1. People will think you are driving around with your brakes on which,
2. While, Yes you will still have the actual brake light, but there is not as big of a change between just tail light and brake application.
you want to catch peoples attention to cause them to react.
Thanks 72Duster440, I had been looking at the Phillips extreme vision, but I couldn’t remember the name. Those looked like they would work well.
 
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LED bulb runs on about 0.5 to 0.75v

The forward voltage of individual LED varies by color, and other manufacturing details. Here is an example table, showing white light at 3.5V.
images.jpeg


Parallel circuits of matched LEDs are possible, years ago series resistors were required, or intensity of each varied.

Most modern automotive LED bulb have built in switch mode regulators that are very efficient. Some bulbs will operate from 10 to 30V DC, and current input reduces as voltage increases, and connection polarity does not matter. Watts consumed is nearly the same, but may decrease with increased temperature. Specifications are not always available at purchase, but with a variable voltage/current bench top power supply, it is possible to carefully test LED bulbs.
 
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The forward voltage of individual LED varies by color, and other manufacturing details. Here is an example table, showing white light at 3.5V
Looks like my memory isn't what it used to be!

Thanks for the clarification.
 
Thanks 72Duster440, I had been looking at the Phillips extreme vision, but I couldn’t remember the name. Those looked like they would work well.


I just looked them up, they have at least doubled in price since I bought them 5 or 6 years ago.
 
Take a look at superbrightleds.com.
lots of info and nice products.
converted my 68 cuda to all LED
 
Take a look at superbrightleds.com.
lots of info and nice products.
converted my 68 cuda to all LED
I converted my '70 Duster to all LED (except for headlights). Tried using the flasher from superbrightleds but it did not work. Got a different one (with a pigtail) and worked fine. Had to reverse the wiring on the parking lights to get them to work, but all in all a great upgrade. Turning the headlight switch to just the parking lights hardly moves the ammeter now.
 
Here is the lower taillight bulb currently in my 66 Barracuda. It's a #97.
IMG_3465.JPEG


Also, these are the LEDs I have for the backup lights. I got them from superbrightleds.com. The taillight housings (and more) are out getting re-chromed or else I would get a pic of them in the dark for a comparison.
IMG_3466.JPEG
 
I'm not sure a #97 would be bright enough, and I can't find an LED replacement in that size. Does anyone have a candlepower/lumen chart to compare these bulb outputs?
 
I'm not sure a #97 would be bright enough, and I can't find an LED replacement in that size. Does anyone have a candlepower/lumen chart to compare these bulb outputs?

Looking on Amazon at Sylvania longlife bulbs, an 1157 is rated 8.3/26.9w, and a 97 is rated at 9.3 w. At least that what it says on the package.
 
Hmmm, so, it actually looks like the 97 is higher wattage than the taillight filament in the 1157.....interesting. I'll have to so some experimenting.
 
The photo of your lower tail light bulb looks like a under dash light bulb.

Or

The bulb and holder for courtesy lights in my 67 dart Convertible.
 
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