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70 Road Runner - Plug & Play LED Tail/Stop Lights?

PurpleBeeper

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1970 Road Runner - I'd like to make my tail lights & brake lights brighter. I've been looking at some 1157 LED bulbs and searched the forums here. I saw a reference about "LED turns signals won't work". So my question....is there a LED 1157 tail/stop light bulb that can be installed in a 1970 Road Runner that fits inside the tail light holes and works without any modification to the wiring? If not, what are my choices to make by tail/brake lights brighter? THANK YOU
 
SuperbrightLED’s.com. You can search for all bulbs in your application.
 
The LEDs tailites for a 70RR need to be of narrow width to fit through the metal enclosure.
I installed LEDs tailites in my 70RR, kept the incadescent amber bulbs in the front OE flasher works just fine.

Just my $0.02...
 
There is nothing unique about the ’70 B-body taillight housing, several other platforms from that time use the same rear snap-in light sockets and pot metal housings. The original 1157 bulbs are about 1” in diameter at its widest point. Have yet to see any 1157 LED substitutes larger than that or have any issue fitting them into rear mounted housings.

Most original thermal flashers require the current flow of a total of three 1157 incandescent filaments to have the correct flash rate. Replacing two of them LEDs can disable flashing or correct flash rates. Electronic flashers are not current/load dependent and are needed for most LED conversions.

Here is another option for ’70 B-bodies.
1970 Plymouth Road Runner Sequential LED Tail Lights
 
There is nothing unique about the ’70 B-body taillight housing, several other platforms from that time use the same rear snap-in light sockets and pot metal housings. The original 1157 bulbs are about 1” in diameter at its widest point. Have yet to see any 1157 LED substitutes larger than that or have any issue fitting them into rear mounted housings.

Most original thermal flashers require the current flow of a total of three 1157 incandescent filaments to have the correct flash rate. Replacing two of them LEDs can disable flashing or correct flash rates. Electronic flashers are not current/load dependent and are needed for most LED conversions.

Here is another option for ’70 B-bodies.
1970 Plymouth Road Runner Sequential LED Tail Lights
As posted previously....
The metal taillite housing for a 70RR has a smaller diameter opening for the bulb mounting and certain LED 1157 replacements are too large to fit through the smaller opening. Check around and U will find various diameter size 1157 replacement. Attached are (2) images as examples of the bigger diameter. Now check image 3, U will see its slimmer size. Also as a final option, Digi Tails has a clever, custome OE PCB module(w/sequential option) with strings of LEDs mounted it is more expensive but has greater briteness.
Regarding flashers there are also LEDs 1157 replacements with a built-in resistor so standard flasher works just fine.
Suffice to say there are multiple options available. I can't comment on other RR years but for my 70RR I have tried each of these options.

Just my $0.02.... :thumbsup:

Image1.jpeg


Image2.jpeg


Image3.jpeg


LEDAssembly.jpg
 
Interesting, your first example appears to be a Speedway Motors branded 1157 replacement, showing a spec’d 1” diameter. If that’s the case shouldn’t have any problem fitting one through your ’70 socket hole. The individual LED orientation on that bulb would not be recommended for a parabolic reflector housing as is the taillight housing in question here, wouldn’t consider that one as an 1157 replacement anyway. Example #2 looks to be smaller than the Speedway Motors led.

If a LED 1157 replacement can’t fit where the 1157 incandescent fits, it’s not really a 1157 replacement.

If I understand this right, to keep the original mechanical thermal flasher functioning correctly, resistors are to be added, or LEDs with resistors internally are used, to restore the current draw to that of the incandescent bulbs? Isn’t one of the big benefits of LEDs, the reduction current draw?
 
If I understand this right, to keep the original mechanical thermal flasher functioning correctly, resistors are to be added, or LEDs with resistors internally are used, to restore the current draw to that of the incandescent bulbs? Isn’t one of the big benefits of LEDs, the reduction current draw?
I think you understand that perfectly. I thought the same thing when I saw some recommendations online to add resistors. Adding resistors corrects the hyperflash problem and the 'bulb out' indicators in cars that monitor the bulb circuit..... But like you said, defeats the purpose of using LED's. Adding the correct flasher, if hyperflash is a problem, makes much more sense.
There are LED bulbs with built in resistors and miniature fans to keep them cool. Now we have fans on our bulbs?! :screwy:
 
I don't know the specific diameter of the tail light bulb mounting for my 70RR but...
In the next day or so I will measure and post it ...
Over the last several years, I have tried multiple 1157 LEDs replacements attempting to increase their briteness but found many are too wide to mount and snap in. I have many samples thrown in a box.
However...
Over the last few years there have been some incredible, creative LED design upgrades that increase briteness, using a sharper lens dispersion and decreased size. And now some of the 1157 replacements LEDs may have up to 75/80 mini-LEDs, together all generating tremendous brightness.
Regarding flashers, as mentioned I am still using a standard flasher in my 70RR with incadescent bulbs in front and LEDs in the rear everything works fine with a nice flashing speed.
I do have a couple of electronic flashers but never installed one as my present standard flasher works just fine.

Just my $0.02... :thumbsup:
 
...found many are too wide to mount and snap in...
For that Speedway Motors branded bulb (example 1 above), while the PCB may likely fit into hole in the housing, I see now that the location of the PCB, so close to the bulb base, could cause it to interfere with the socket clips, preventing the socket from being able to snap in to place. That one I would rule out as a true 1157 replacement on that issue only.
 
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1970 Road Runner - I'd like to make my tail lights & brake lights brighter. I've been looking at some 1157 LED bulbs and searched the forums here. I saw a reference about "LED turns signals won't work". So my question....is there a LED 1157 tail/stop light bulb that can be installed in a 1970 Road Runner that fits inside the tail light holes and works without any modification to the wiring? If not, what are my choices to make by tail/brake lights brighter? THANK YOU
I thought that was the number and size used or am I mistaken? I remember buying that specific number at auto parts?
 
Regarding the LED string module supplied by DigiTails, I actually have this part. The modules are designed to drop into the factory tail light. To connect to the OE wiring harness, they provide output wire leads and male bulb socket bases are available so the entire assembly plugs into the OE wiring harness. I attached a picture of the LED modules....

Just my $0.02... :thumbsup:

RR70_DigiTails.png
 
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For that Speedway Motors branded bulb (example 1 above), while the PCB may likely fit into hole in the housing, I see now that the location of the PCB, so close to the bulb base, could cause it to interfere with the socket clips, preventing the socket from being able to snap in to place. That one I would rule out as a true 1157 replacement on that issue only.
OK. Here are the LEDs I found that work great for my 70RR and slip right into the factory housing. They are sold in pairs by Amazon for about $14.00 From the picture U can see how slim they are and can be direct replacement for the standard 1157 bulb.

Just my $0.02... :thumbsup:

LEDs_1157.jpg


LEDs_1157_2.jpg
 
This has been INCREDIBLY helpful!!! If I'm understanding this all correctly (?)
1. Not all LED 1157's fit. I kind of figured this out when I looked at superbrightleds.com. They all had the same socket, but different sizes. 1" diameter sounds about right. superbright had one 1" dia. LED bulb with a "glass ball covering" over the LED's....it "looks" more weatherproof???
2. If you're trying to reduce amp load, LED's make a ton of sense.
3. It sounds like with the tiny amount of resistance in an LED bulb, that "confuses" the stock flasher. That explains why with all regular bulbs, if one turns signal bulb burns out, that side flashes faster than normal. Swapping out one regular bulb for one LED and the faster flash might still be OK. Swap out 2 LED's or more & maybe they don't flash at all? (without a LED flasher)
 
This has been INCREDIBLY helpful!!! If I'm understanding this all correctly (?)
1. Not all LED 1157's fit. I kind of figured this out when I looked at superbrightleds.com. They all had the same socket, but different sizes. 1" diameter sounds about right. superbright had one 1" dia. LED bulb with a "glass ball covering" over the LED's....it "looks" more weatherproof???
Not only the weatherproof aspect but the way we need to push and twist the bulb to get it in the socket, I wouldn’t want to put that stress directly on the LED’s that are soldered to the circuit boards in the bulbs - you might break the solder joints or rip some LED’s off. I want a cover or something to grip on, other than the LED’s
 
Just replaced the running lights, brake lights and turn signals with leds on my 71 road runner. I recommend the use of red leds where the housing lens is red and orange leds on for the orange housings. For the turn signals upgrade to a digital timer, the lights will flash consistently and won't slow or stop at low rpms. You will need 2 flashers 1 for turn signals and 1 for the hazards. see attached:

20231129_070314.jpg
 
My road runner required this adapter to change polarity on the timer but my barracuda did not.

flasher adapter.jpg
 
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