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]

The test I did with 10 LEDs putting out about 40LM each didn't achieve the brightness I am looking for although they were bright as hell.

One item that is designed into all LED lighting is proper lense and/or reflector designed for the LEDs. This is true on all factory-designed LED lights.

So I've been looking into reflectors for LEDs and ran across the following thread on CandlePoweredForum discussing LED brake and tail lights.

I don't know any of these guys nor do I know their backgrounds but they sound quite knowledgeable about automotive lighting and LEDs.

Seems all of the "experts" on this thread indicate that the drop-in LED replacement bulbs are not very good and may even be illegal to replace filament bulbs with LED drop-in's in tail and brake light fixtures in some states.

They bring up good points about brake/tail light modifications and ramifications concerning liability if one is involved in an accident.

CandlePoweredForum Thread

In short, this LED implementation that I am doing could be illegal since it involves modifying a safety feature on an automobile. If I sell this to someone and they have an accident or get pulled over for having illegal lights, would I be liable? Maybe I'd have to state "for off-road applications only".

Here's another thread on LED automotive lighting and lenses.

Photonics Thread