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Freq
02-09-2008, 04:34 AM
So I thought as fun side project I'd try to create a set of LED break lights, turn signals, etc. If possible it would be a bulb replacement or a drop in kit. Something with as little modification as possible. I believe the voltage running into the sockets is 12v (please correct me if I'm wrong). I'm not sure how many LEDs would be enough to put out enough light to be safe, legal, and attractive (IE worth the time).

I got an LED flashlight for Christmas which has 9 LEDs and enough power to create a nasty bleach for a few minutes, so I shouldn't need more than 9 per light. I'm thinking 6 to start, and adding more if I need to. So if the power going to the light is 12v, the LEDs I'm looking at (wide-angle red LEDs from Radio Shack) have an average load of 1.7v, and 20mA current, then the circuit would look like this: [[Positive]] - [[100Ohm resister, 1/8W]] - [[LED]] - [[LED]] - (etc.) - [[Negative]]

Radio Shack's website says each LED is 800mc, so 800mc x 6 = 4800mc = 4.8 candelas. It's a nice amount of power, but I don't know how it compares to a normal tail bulb. If that's not enough I can create a parallel circuit which would double the LED count and double the candelas (9.6).

The other issue I'm afraid of is that the LEDs aren't going to look like a solid mass of light, it's going to look like 6 dots. I know if you roughen up one side of the plastic lens it will make the whole thing glow. Does anyone have experience with this?

Has anyone else tried this or do I get to play pioneer? I hope the lights are still on my scrap yard's 744 once I have the money to start doing this.

RvolvoR
02-09-2008, 04:40 AM
check out the LED conversion forum on hidplanet.com it will help you out a bunch

Freq
02-09-2008, 05:23 AM
check out the LED conversion forum on hidplanet.com it will help you out a bunch

Holy crap, thanks a lot. I didn't realize I'd have to make the circuit stable at 14.4v. That saves a lot of time and effort. Once income tax rolls around (:oogle:) I'll start working on this.

You have to register to the forums to see the information, so I'll post the diagram here in cast yous guys want to try it, too.

They're saying to use 16 LEDs with a 3700mc brightness and a 70 degree viewing angle. The 16 LEDs was for corner lights, so I assume the same number would be used for blinkers. Not sure about break lights. Suppose it depends on size. We'll see.

[|Positive|] -- [[LED]] -- [[LED]] -- [[LED]] -- [[LED]] -- [[330 ohm resistor]] -- [|Negative|]
[|Positive|] -- [[LED]] -- [[LED]] -- [[LED]] -- [[LED]] -- [[330 ohm resistor]] -- [|Negative|]
[|Positive|] -- [[LED]] -- [[LED]] -- [[LED]] -- [[LED]] -- [[330 ohm resistor]] -- [|Negative|]
[|Positive|] -- [[LED]] -- [[LED]] -- [[LED]] -- [[LED]] -- [[330 ohm resistor]] -- [|Negative|]

The [|Positive|] symbols are the same wire. It's a 4x4 array, but writing it out in ASCII isn't something I really wanted to do. Same with [|Negative|].

Marek
02-09-2008, 09:46 AM
Dude, i dont want to burst your bubble, but you can get all those lights and side markers and basically any light bulb around your car in 12led mode... With the existing socket to top it off.... Im just not sure its worth your time and effort to make these :(
I'll go buy 1-2 to show you what im talking about maybe i just didnt understand what you were saying :)

mblue240
02-09-2008, 12:45 PM
Or you could just go to superbrightleds.com and buy them, much easier than making all of them yourself.

2fast242gt
02-09-2008, 01:04 PM
i have somthing like 36 led brake lights in my 242 now:cool:

Freq
02-09-2008, 01:32 PM
Or you could just go to superbrightleds.com and buy them, much easier than making all of them yourself.

SuperBrightLEDs.com says that the drop-in LEDs aren't going to be as bright as the bulbs you're replacing. You'd have to create a larger array to get a brighter result.

LED bulbs are generally not as bright as standard incandescent bulbs, they have many advantages over filament bulbs (longer life, faster on/off times, lower power consumption, more vivid colors) but brightness is not one of them.
They are generally not as bright but some of them with large numbers of LEDs, will appear brighter than filament bulbs.
As an exception, our new 3 Watt and 5 Watt Luxeon LED car bulbs are as bright or brighter than most standard filament car bulbs.

Also, I like soldering shat together. :) And I'm looking to spread the light throughout the lens rather than just from a single spot so it has a more uniform glow.

2fast242gt
02-09-2008, 01:51 PM
yes, thats why i got the best led bulbs. they have a tun of led's and spred the light everywhere. there are led's on every part of the bulb.

YURPLES
02-09-2008, 05:49 PM
^^^^^ Link? ^^^^^ I heard that when you replace your turn sigmals with LED's they will blink hella fast.

pinguin
02-09-2008, 05:56 PM
^^^^^ Link? ^^^^^ I heard that when you replace your turn sigmals with LED's they will blink hella fast.

Unless you get an LED flasher or ballast resistor, yes. Yes they will.

Freq
02-10-2008, 03:39 AM
Unless you get an LED flasher or ballast resistor, yes. Yes they will.

Would adding an extra resistor to fix the blinker switch dim the LEDs?

1stRaven
02-10-2008, 04:58 AM
I use this in my 740 with is fitted with led's on all the turn singles.

http://www.ultraleds.co.uk/complete-flasher-unit-stops-fast-flashing-indicators-p-978.html

With the hova's, I can't seem to get the red led bulbs to work for the brake lights but the one in the high level brake light works fine. I'll see if I can dig out a video for you.

1stRaven
02-10-2008, 05:13 AM
btw, take a look at this thread for ideas

http://forums.linear1.org/index.php?PHPSESSID=5a5d0732baf1a77cb34a529305bf3d 48&topic=357.0

YURPLES
02-10-2008, 01:00 PM
So where is a good place to by the direct replacement led bulbs?

Marek
02-10-2008, 01:33 PM
So where is a good place to by the direct replacement led bulbs?

In canada we have this place called Canadian Tire and they have em all for all cars its like a giant tool store with a huge car section. WHere you get your car parts :)

Freq
02-10-2008, 01:38 PM
So where is a good place to by the direct replacement led bulbs?

SuperBrightLEDs.com is always a place I see highly rated.

1stRaven
02-10-2008, 03:51 PM
i got mine from ultraleds.co.uk but best to buy in your own country.