Taillight Conversion from 1157 to 3157 bulb with Photos

Stock FSJ Tech Area

CadChris
Posts: 5
Joined: Sun May 16, 2021 3:52 pm

Re: Taillight Conversion from 1157 to 3157 bulb with Photos

Post by CadChris » Sun May 16, 2021 4:38 pm

Sorry for the double post......I added additional info in the last paragraph above on LED's......

User avatar

tgreese
Posts: 4732
Joined: Fri Jun 08, 2012 6:31 am
Location: Medford MA USA

Re: Taillight Conversion from 1157 to 3157 bulb with Photos

Post by tgreese » Sun May 16, 2021 6:05 pm

It's an issue with the forum. Click submit once and a single copy will eventually show up.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 FCA Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

User avatar

ProTouring442
Posts: 641
Joined: Sat Mar 23, 2013 10:28 am
Location: Harriman, Tennessee
Contact:

Re: Taillight Conversion from 1157 to 3157 bulb with Photos

Post by ProTouring442 » Mon May 17, 2021 5:59 am

You ever wonder what medieval cook looked at the guts of a pig and thought, "I bet if you washed out that poop tube, you could stuff it with meat and eat it."

http://www.facebook.com/william.k.elliott.7

http://www.WilliamKElliott.com

My LY5/4L60E swap: http://www.fsjnetwork.com/forum/viewtop ... =12&t=1850


CadChris
Posts: 5
Joined: Sun May 16, 2021 3:52 pm

Re: Taillight Conversion from 1157 to 3157 bulb with Photos

Post by CadChris » Mon May 17, 2021 2:02 pm

That bulb has been discussed heavily and not recommended to be safe by the experts on the Candlepowerforums. Just saying. It's a halogen bulb, runs way too hot, high amp draw on original wiring at 3.9 amp draw, and can melt wires. Probably your buckets are made out of metal, but could melt the lens if sitting on the brake pedal for a while and/or melt wires in the worst scenario. Most likely the "rise-time" is very slow which at high-way speeds is really delayed before coming up to full brightness if you land-on the brakes. This bulb probably causes a 1/4 sec. delay which is probably 15' of response time for the driver behind you to react! They have a formula on the Candlepowerforums they refer to all the time which the LED bulbs are instant-on and prevent this delay. Like I mentioned, they only recommend the Sylvania ZEVO's but you must do a remedial evaluation at all viewing angles/distance to see if the LED retrofit brightness falls-out at different viewing angles.

But on those H1157 bulbs, those experts also said the filaments are not precisionally nor properly placed in the correct locations according to the specs of a 1157 Bay15d style bulb which I guess throws-off the focusing for the reflector bucket. I always wondered how much precision is needed with a parabolic reflector going thru a lens with focusing optics, but those guys are the lighting engineering experts and know their photometry. That's why they recommend the HONDA 3496 bulb as the best upgrade in place of any 1157/2057/2357 bulb since it was such an advanced designed bulb from Stanley of Japan. I guess it also has a much lower amp-draw (faster rise-time) vs. a conventional 1157 bulb. I've been personally researching amber bulb paints to make a Honda 3496 amber to be used for front -signals in my car since the Honda bulb is only available in clear......

Probably to get the most out of that H1157 halogen bulb, it's best to run new heavy gauge wiring to the rear-lamps thru a good TYCO/Bosch relay so full amperage is not going thru the factory headlamp switch which might not able to carry a heavy load of 8amps for a long period of time if someone is sitting in traffic on the brakes for a while.......


Triumph215
Posts: 133
Joined: Thu Jan 07, 2021 8:42 pm
Location: Monterey, Ca

Re: Taillight Conversion from 1157 to 3157 bulb with Photos

Post by Triumph215 » Mon May 17, 2021 8:04 pm

I haven't made it to dim tail light bulbs yet but they are on my TTD list and will use this when the time comes.
Thanks !
1964 Triumph TR4 with 1964 Olds 215 heart transplant
1977 Wagoneer
2009 BMW GS1200


Hobart
Posts: 53
Joined: Wed Aug 26, 2020 2:34 pm
Location: Chicago, IL

Re: Taillight Conversion from 1157 to 3157 bulb with Photos

Post by Hobart » Thu Jun 17, 2021 9:21 am

Great info here! Thanks to all!
Bill

1979 Wagoneer
1959 Bel Air
1968 Nova
1972 Eldo ragtop
1980 Z28


Nikkormat
Posts: 3621
Joined: Sun Jun 29, 2014 11:45 pm
Location: Salt Lake City

Re: Taillight Conversion from 1157 to 3157 bulb with Photos

Post by Nikkormat » Tue Jun 22, 2021 5:55 pm

Thank you CadChris!!
Gabe, "reformed" Jeep hoarder.


CadChris
Posts: 5
Joined: Sun May 16, 2021 3:52 pm

Re: Taillight Conversion from 1157 to 3157 bulb with Photos

Post by CadChris » Wed Jun 23, 2021 4:43 am

Glad I can help ya' all........

Post Reply

Who is online

Users browsing this forum: Bing [Bot] and 3 guests