LED tails vs Standard tails for gas mileage? - Fuelly Forums

Click here to see important news regarding the aCar App

Go Back   Fuelly Forums > Fuel Talk > General Fuel Topics
Today's Posts Search Click Here to Login
Reply
 
Thread Tools Display Modes
 
Old 05-26-2010, 07:02 PM   #1
Registered Member
 
Join Date: Apr 2007
Posts: 336
Country: United States
LED tails vs Standard tails for gas mileage?

I see many cars with LED tailights, and most of them have about 15-20 led's on each brake light to replace 1 or 2 standard bulbs on each side. does the energy used in the LED's exceed the standard lightbulbs?

for example: a 05 honda accord has 1 bulb for the brake light (2 total) on each side, while a 06 accord has 16 LED's on 1 side (32 total). does this actually save any energy or is it just for looks.
__________________

civic94 is offline   Reply With Quote
Old 05-26-2010, 07:13 PM   #2
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
It may save some energy. LEDs can produce the same light with less energy usage. However, they are probably tacked on to a wasteful system that ends up using more energy. That's how OEM automotive engineering often works, in my experience.

OEM LEDs are there for perceived value, looks, and maintenance (since LEDs have a longer service life than incandescent).
__________________

__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 05-27-2010, 12:09 PM   #3
Junior Member
 
willix's Avatar
 
Join Date: Jun 2010
Posts: 26
Country: United States
Location: pigseye, mn
The balance of cost vs. re-lamping & the gains may be questionable. It will relieve the system of a few of amps and also extend longer alt. life. This played a big part in savings on trucks I work on with 30 or so lamps on the rear alone that are on the brakes 1000 times & flashers allday long in a day picking up garbage. To re-lamp all is very expensive and although LED's are warranted very well they have issues the same conventional bulbs. In a car reliability is better i would imagine.
willix is offline   Reply With Quote
Old 05-27-2010, 06:20 PM   #4
Registered Member
 
GasSavers_BEEF's Avatar
 
Join Date: Apr 2008
Posts: 1,831
there is also a safety advantage. redundency is often used for safety and in this case, there is more than you can shake a stick at.

this way, if one bulb goes out, you still have light on that side.

a side note though. I looked into aftermarket LEDs and noticed that when replacing bulbs with LED boards, on some of the lights (like the turn signals) you are required to use load resistors so the cars computer knows there is a light there and it is not burnt out. it needs to see a certain amount of current draw to recognize that there is a bulb present. obviously not a problem on OEM stuff.
__________________
Be the change you wish to see in the world
--Mahatma Gandhi



GasSavers_BEEF is offline   Reply With Quote
Old 05-27-2010, 07:21 PM   #5
Registered Member
 
GasSavers_JoeBob's Avatar
 
Join Date: Oct 2007
Posts: 698
Country: United States
An 1157 bulb draws .6 amp (taillight filament) and 2.1 amp (brake light filament). 12v x .6 amp = 7.2 watts. Other incandescent tail lamps are probably similar. In other words, about 1/100th horsepower per bulb (1 hp = 746 watts). I doubt you'll ever be able to measure a FE difference. And, many LED taillights are strobed, which makes many of them (especially the older OEM types) very distracting...at least to me.

OTOH, LEDs should last a lot longer, and come on instantly, which may possibly reduce rear-end collisions...and that's always a good thing.
__________________
"We are forces of chaos and anarchy. Everything they say we are we are, and we are very proud of ourselves!" -- Jefferson Airplane

Dick Naugle says: 1. Prepare food fresh. 2. Serve customers fast. 3. Keep place clean.



GasSavers_JoeBob is offline   Reply With Quote
Old 05-27-2010, 10:33 PM   #6
Registered Member
 
Join Date: Jun 2009
Posts: 29
Country: United States
Doubt you'll ever recoup the cost you spend on purchasing replacement tails with the reduced energy/$ it costs you to run them.
deschlong is offline   Reply With Quote
Old 05-28-2010, 12:34 AM   #7
Registered Member
 
fowljesse's Avatar
 
Join Date: Mar 2008
Posts: 188
Country: United States
Here's what I'm thinking about all of this; I am going to put on an underdrive crank pulley, so all of my belt driven things will turn slower. LEDs won't tax the slower moving alternator as much. I'm replacing every bulb that I can with LEDs, and have replaced the 9004 headlights with HID projectors.
fowljesse is offline   Reply With Quote
Old 05-28-2010, 07:00 PM   #8
Registered Member
 
kamesama980's Avatar
 
Join Date: Nov 2007
Posts: 742
Country: United States
Location: Columbus, IN, USA
Send a message via AIM to kamesama980 Send a message via Yahoo to kamesama980
simple test: get a voltmeter gauge installed in the car. if, with the underdrive setup, the system voltage is over 13v at the lowest warm idle but when you turn all the lights on drops below 13v, then worry about current draw. till then you aren't 'overtaxing' your electrical system
__________________
-Russell
1991 Toyota Pickup 22R-E 2.4 I4/5 speed
1990 Toyota Cressida 7M-GE 3.0 I6/5-speed manual
mechanic, carpenter, stagehand, rigger, and know-it-all smartass
"You don't get to judge me for how I fix what you break"
kamesama980 is offline   Reply With Quote
Old 05-28-2010, 09:31 PM   #9
DRW
Registered Member
 
Join Date: Oct 2006
Posts: 615
Country: United States
I like my LED tail and running lights because I like to EOC at night and it doesn't drain my compact 15 pound battery as much.
__________________
Dave W.
DRW is offline   Reply With Quote
Old 05-28-2010, 10:55 PM   #10
Registered Member
 
fowljesse's Avatar
 
Join Date: Mar 2008
Posts: 188
Country: United States
Quote:
Originally Posted by kamesama980 View Post
simple test: get a voltmeter gauge installed in the car. if, with the underdrive setup, the system voltage is over 13v at the lowest warm idle but when you turn all the lights on drops below 13v, then worry about current draw. till then you aren't 'overtaxing' your electrical system
Thanks! I wouldn't have thought of that.
__________________

fowljesse is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
My experience with Airtabs JudithGordon Experiments, Modifications and DIY 10 01-13-2019 09:32 AM
MPG versus air temperature and Altitude MensaMike General Fuel Topics 6 06-21-2011 06:16 AM
Steam cleaning the intake trollbait General Maintenance and Repair 1 04-12-2008 02:53 PM
Any ideas how to install this? Compaq888 General Maintenance and Repair 0 12-21-2005 01:46 PM

» Fuelly iOS Apps
» Fuelly Android Apps
Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 03:39 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.