LED Taillights, Custom Made for the 914 Options

[Spoke]

I've wanted to convert my 914 taillights to LED for a while but never got around to it.

Finally I started working on the design of the taillights. This will be a single custom PCB for each side and will have all the LEDs and control circuits on it. One PCB will be used for both sides.

The plan is to remove the existing plastic reflector and bulb assembly and mount a custom board in its place. With proper standoffs, I should be able to mount the board using the same 2 screw holes that secure the reflector.

I'm trying to decide now how many LEDs to use for each purpose. Right now, I have 8 LEDs for the backup lights, 20 LEDs for the running/Brake lights, 24 LEDs for the turnsignals, and 4 LEDs for the side marker.

I've been observing modern cars with LED taillights and some use a few LEDs (like 8) and some a lot (+20).

I would like your opinions on how many LEDs you think would be good to use. On the board below, the LEDs are spaced about 0.7 inches apart. These will be medium brightness white LEDs. (I'll let the lenses provide the color).

The first cut at the board is shown below for the driver's side. The side marker LEDs will be right angle LEDs pointing out the side of the board. They can be seen on the extreme left side of the board.

If these work out, I could manufacture them for World members. One thing though, they won't be cheap. The LEDs are about $0.50 through Digikey and there are more than 55 LEDs on each right now. Plus there's 2 dc-dc converters for providing constant current for the tail/brake and turnsignal LEDs.

Cheers
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[Spoke]

Thanks for the replies. I'll try to address each question comment here.

"Nice. Are you going to follow up with front light assemblies?"

Haven't thought about it yet. Which function would the LEDs replace/add? Turnsignals? Running lights?

" I like to see lots of leds. I don't like the look of a few bright lamps. "
AND
"rather see more than less LED's as these cars are hard to see."

Good to hear. I like the "panel" look to modern LED tail/brake lights.

"Do a search. Someone was putting quite a bit of effort into doing this a couple years ago."


LED Tail Lights

You found the same one. Not sure how it worked out. I don't want to modify the housing so mine will screw into the existing mounting holes and use the existing wiring. That's the plan at least. I will have to deal with the lower current draw to keep the flasher happy. I may have to add a power resistor to get enough current. The goal is to do LED lights, not save power.

"I'd do the math with the brightest LEDs available and see what the cost winds up at."

Agreed. This won't be cheap. Individual LEDs are expensive (> $0.50 each). Plus I'm using dc-dc step-up converters to get very stable LED currents regardless of the supply voltage. They will add $15 to the BOM cost.


"Or, You could just do this....."

The goal is a cool LED panel like modern cars. LEDs allow the modern automotive designer to design all kinds of light panels like pyramids, slanted boxes (parallelograms), perimeter tails with brakes in the middle, eye brows, etc.

"you might consider a "back off light" or "taillight flasher"

Neat idea. It might not be that hard to put this in.