anyone think about cutting out the 3 holes in the Z in the strut tower bar in the trunk and installing l.e.d.s or a light of some sort? seems like it wouldnt be too hard and it would look cool in my opinion through the hatch glass at night. you could wire them to the rear tail lights so it would come on with your headlight or parking lights. is that strut tower cover hard to get off? what about all that plastic? they sell blue l.e.d.s at autozone that run on 12v and would fit right in there......any opinion good or bad?

 

sounds cool for a show car

i was thinking about doing that but instead of led's on the actual bar, i was gonna just have lights pointing at the bar.

 

what is involved in removing that Z cover and the black plastic on the tower? anyone done it

 

there are better places to get LEDs than autozone, someone said the prices on them, they were CRAZY.

anyway, if you need any help I got blue, white and amber LEDs laying around and the proper resistors that I could put together for you.

but the hard part would be getting the power source in there, particularly from the tail lights, itd be pretty cool to have em come on with the trunk light for those at shows that show off their stereo equipment.

 

the only thing cool about the ones at autozone is they are blue and come in packs of 3 or 4 i think. i could run a wire down the strut tower under the plastic? what would be the best way to mount them in the 3 Z holes so it looks good in the daylight?

 

Very good idea. I had that in mind before. Make the LED go with the bass of the sound system.

 

well I dont know if autozone has them prewired or what, but you can get blue, and resistors are pretty easy to get.

as for mounting, just drill the hole and glue the LED right into it.

you can use hotglue or silicone, the latter being stronger but it takes a bit longer to set(2 hours to be "dry" overnight to be DRY.)

 

what about superglue...no good?

 

well it has very little "substance" to it is the problem, its also very brittle. the nice thing about hot glue and silicone is that its a very thick glue(both are about the same consistancy) but they let you get a nice bead around the LED for some strength, where the superglue will only hold in direct contact of the LED and the plastic.

also there is a chance of the superglue melting the plastic peice, hard to say for sure, but itd be one of those thing where youd wanna test it before using it.

I have personally tried superglue and rubber cement in the past, the superglue worked somewhat, and only becuase I used rubber grommets to assist in the surface area for the glue to work on.

every since Ive used silicone only. it can be bought in homedepot for a few bucks.

 

ares - how do you know what size resistor to use and which led's to make this work? I LOVE the idea... but i'm pretty sure that just hooking up the led's to 12v source will cause them to burn out right? is there a formula or anything to see which led's/resistors should be used and when? i know you're the resident led genius around here

 

the l.e.d.s at autozone are made to run off 12vdc

 

I have amber lights in my strut bar that lights up when the stereo is on , I put Amber LED's in easy to do you can run it off of any power source also have done all my "Z" Emblems as well .

 

if you dont go with the autozone, there are various online calculators to do thw work for you. just go to google and search "LED resistor calculator" their all the same.

1/2watt will be fine and should be no problem finding them at radioshack for 5/.99$. you can run 3 LEDs in a series no problem, so youd only need 1 resistor, off the top of my head I know I use a 470ohm for 3 ambers and a 220 ohm for 3 whites.

 

Steve (Z2thdr) has done the same thing as Terry (same shop I believe) and I took a couple of pictures when he was up here last week. First is the Z on the strut bar and the second is the door handle. The door handle is really really cool and very well done! Unfortunately these were taken during the day so you can't really see the lights too well.

 

Figuring out the necessary resistor is a fairly simple calculation, as long as you know a few simple things.
1) Most car batteries will be around 12.0-12.5V, and the alternator will crank out around 13.5-14.5V when running.
2) R=V/I (or Resistance = Voltage / Current)
3) P=VI (or Power = Voltage * Current)
4) Different colored LEDs have different voltage drops
5) LEDs vary, but you generally can't go wrong with 10-20 mA of current
6) Putting LEDs in series can be a good thing

Your typical connection is from the battery to a resistor/LED to ground. The resistor needs to "drop" any voltage not dropped by the LED. The less voltage that the resistor needs to drop, the better, so putting several LEDs in series helps us out.

For example, let's take the 3 LED example from above using 3 red LEDs. Typical red LEDs have voltage ratings of around 2.0V (I've used some as low as 1.5V and some as high as 2.3V, so read the package). So, if we put 3 of them in series, we have a voltage drop across the LEDs of 6.0V (2.0V * 3 LEDs).

If we assume a 14.0V alternator, we need to drop 8.0V across the resistor (14.0V alternator - 6.0V LED drop).

Let's assume our LEDs work well with 20mA of current. Since they're in series, they all receive the same amount of current through them, but the resistor is what determines this current. So, using R=V/I, we have R=8.0V/0.020A, or R=400 ohms.

Now that we know the resistance, we need to calculate how much power it should be able to handle. So, we turn to our last equation, P=VI. We have P=8.0V * 0.020A, or P=0.160 Watts. You always want to "derate" resistors a good 25% or more, so we could get away with one that is designed to handle 0.250 Watts, or 1/4W.

So, if I were to take a 400 ohm, 1/4W resistor and put it in series with 3 red LEDs, I'll get a nice, bright glow from some pieces of plastic that shoudl last longer than the car itself.

My apologies for the long example, but after a trip or two to Radio Shack, you should easily be a pro at setting these up for yourself. No need to buy $10 LEDs at AutoZone

For blue and white LEDs, the voltage drop tends to be more along the lines of 3.0-3.5V (since white LEDs are nothing more than blue LEDs doped with a white phosphour).

If anyone has any specific questions, I'm glad to help out where I can. I tend to spend more time on s2ki than here, but that may change.

 

Thanks for posting this information and I have no doubt that you have helped out a lot of people. But for the first time in my life, I think I now know how Ralph Wiggum feels. Anyone have any paste...

 

you can cheat too.

he gave a great write up and its good to know whats going on, but the take home message is

positive ----- resistor ------ LED ------- ground

now if you have more than one LED, you add together their voltage draw. assuming your talking amber, its around 2volts, so if you have 2, then you using 4 volts, 3 is 6, you cant put more than 7 in series, cause thats 14 volts.

simple right?

so if you have 3, what resistor?
http://ourworld.compuserve.com/homep...Bowden/led.htm

this one adds together the volts for you, 3 LEDs, 2 volts each 20 mA. gets you the proper resistor.

as for watts, get the next common size up, you can never have too many watts, just too few, 1/2watt is good for most any LED setup.

 

macgyver - are you the one that made the lighted wind deflector for the s2k? that thing is absolutely amazing and if that's you - you need to spend ALOT more time over here

 

now i'm getting it a little. so can we conclude that you cannot have more than 7 led's wired in series?

also - i'm trying to remember back to my hs physics days... is series wiring like this?

source led led led
+.........+ -.........+ -..........+ -
-............................................:


sorry for the extremely crude drawing - it's late. =)

 

Man that door handle LED thing is sweet, it would sure help when looking for the door handle at night. but would look even better at shows.