LED Stop/Brake Lights - don't bother?

[Heuer]

The LED bulbs have arrived and they are quite impressively built with 18 rear facing and six radially mounted red LED's.

When fitted to the car they are, however, an epic FAIL! These are the side lights (LED on right) and they do seem to work ........


until you move off centre:



From the viewpoint of any driver overtaking you or vice versa your lights will completely disappear. A truck or 4x4 directly behind you will also not see any visible light because of their height. These things are down right dangerous and whilst they may work on newer cars with differently designed lenses they should never be used on an E-Type.If you have fitted them I suggest you remove them ASAP!

[Mark Gordon]

In the last photo, your instrument lights are very impressive. Maybe hook them up to come on as a warning to those behind you when you step on the brakes?

[Heuer]

That is a subject of another post Mark. They are the same LED strips as I used in the minor instruments but are way too bright. I have just bought a dimmer for them:


As you say maybe I should have fitted those to the side lights!

[adv_rider]

I think something like this should be used. And better the red colored one.

http://www.autoanything.com/lights/65A5617A0A0.aspx

http://www.autoanything.com/lights/65A5698A0A0.aspx

Note: I mean the 360? bulbs, not necessarily this brand which was the firts thing I found to use as an example.

[Heuer]

Finally found a diagram of the light output of side/stop LED bulbs. This is very much like mine although in my case the LED's are all red:


It also seems you can buy side/stop bulbs with either an 18 degree beam angle or a 100 degree beam angle. Also worth understanding is the definition of an LED 'beam angle' which is the point at which light output drops below 50%. This confirms what I am seeing - as soon as you move off centre the lights start to dim.

If you want more visibility stay with the tungsten side/stop bulbs and add an LED array as a third brake light. Mount it in the number plate recess but make sure it is angled upwards to mum's in 4x4's can see it! Angus and I were discussing the idea of wiring the reverse light to act as a third brake light by using a red LED bulb. Personally I am going to stick with standard bulbs all round bar QH headlights.

[Heuer]

Dave Kerr has installed the Classic Auto LED's http://www.classicautoleds.com/JAG_XKES1.html set in his S1 and sent me these pictures. I specifically asked him to take some off-centre shots to see if there was a problem viewing the lights off-axis:






And here is the difference between tungsten (left) and LED (right) brake lights:


So it does indeed seem Classic Auto LED's have produced a workable solution by using red rather than white LED's. The only fly in the ointment is the rear indicators are also red so can't be used in the UK/EU. The front side/indicators would be OK here because they use amber LED's for turn and white LED's for side. They are very expensive though - $227 + shipping for the rears (red indicator board included unfortunately) and $118 + shipping for the front (amber LED's so OK).

It looks like the red lenses on the E-Type do not work well with the white LED's as they filter too much so the trick is going to be to find stop/side bulbs using red LED's. These might do the job: http://www.autobulbsdirect.co.uk/380-Su ... -Bulb.html

[Gfhug]

David, you've done a lot of research for which we are all grateful.
As red LEDs seem to be required, what about these?:

May not be as good as those upgrades from the US but could be better than the old fashioned filament bulbs.

Geoff

[Heuer]

Geoff

I would suggest paying a bit extra and going for the 60 LED versions rather than the 45 LED.: http://www.autobulbsdirect.co.uk/380-Su ... -Bulb.html Check the height will clear the lens before buying though:


You will notice the latest generation of LED's are small white squares rather than the older bullet shape. When they are yellow (coated with yellow phosphor) they produce white light from blue LED's.

[Gfhug]

And these seem like an option for the reverse lights, 42mm looks like the right size for the Elan rears. http://www.autobulbsdirect.co.uk/264-le ... white.html

Not trying to do Marek out of business on the other thread, but....

[Mountain King]

I have no idea as to the quality of the following, but I was very happy with the radiator shroud and fan I purchased from V12s
http://www.v12s.com/indxcc.html

[Dave K]

Just to update the thread, XK's do offer amber for the rear indicators in fact they produce a full UK compliant kit unfortunately they made a mistake when they sent mine. I will have the amber ones shortly. The front indicators also allow for the front indicators to be used as DRL's but no good over here since they would be amber not white, shame really.

Dave

[Gfhug]

Have ordered the red brake and white festoon type reverse bulbs and will post comments when they are fitted. Autobulbs also have type 382 amber LEDs which fit S2/3 and Elan indicators, not sure whether they are suitable for the S1 rear indicators: http://www.autobulbsdirect.co.uk/382-Su ... -Bulb.html Going to see how good the brake and reverse lights are before opting to try the indicator bulbs.

[Heuer]

Please let us know how you get on. Again pictures (which can be difficult) from several angles with lED on one side and tungsten on the other would be good.

[Mark Gordon]

"...lED on one side and tungsten on the other would be good." Now David, would that be before or after the IED was set off?

[Heuer]

[Heuer]

Done a bit of research on the stop/side LED light issue. It seems the Classic Auto LED's Co. array work because they are designed for light volume rather than light intensity. By covering the vertical surface with multiple LED's they overcome the 90 degree viewing angle limitation we find in single point bulb replacements. My thought is to use splash-proof red 60 LED/metre 14w/12v SMD5050 adhesive strips on a suitable shaped substrate (e.g. paxolin)


http://www.ledlightszone.co.uk/led-tape ... 30pcs.html

The tape is 10mm wide and can be cut every 3 LED's so there should be room for five strips of three - two for side plus three more for stop on an S1. Now that does not sound much - 15 LED's in total compared to the 48 on the commercial board - however the new SMD5050 chips have three LED's per chip ('tri-chips') so that gives us a total of 45 points of light (SMD = surface mounted device) at 18 lumens each = 810 lumens theoretically for stop per side (but at 40% efficient = 324 lumens). The strips already incorporate overload and polarity reversal protection so simply a case of wiring all six strips to illuminate on brake and only two (alternate) strips for side light.

This stuff would be a good substrate as it is cheap and easy to work with:

http://www.verotl.com/en/category/strip-board

If some kind soul could provide a cutting template of the Classic Auto boards it would simplify making them up no end Total cost for the project would be about ?25 and you would have sufficient LED strip for five S1's.

[Dave K]

:D David I'll PM you.

Dave

[Heuer]

I thought something like this:


Veroboard with copper strips would simplify wiring.

[tonyabacus]

As a newbie following this thread I now know I am in good company as Heuer has the same colour playthings in his toy room as me, one of mine is also yellow but will not be donating its rear lights to the E type! Good read
Tony

[Heuer]

I have just about given up on LED replacement bulbs so I have come up with another cunning plan!

According to the Bosch Automotive Handbook (7th ed) a 21W Brake bulb puts out 460 lumens and a 5W Tail light 50 lumens (surprisingly low I know) when new. My research into headlights tells us if we consider output at 13.2v to be "100%" rated output: when operating voltage drops to 12.54v bulbs produce only 83 percent of their rated light output. When voltage drops to 11.88v bulb output is only 67 percent of what it should be. And when voltage drops to 11.22v bulb output is a paltry 53 percent of rated output. So our 460 lumen stop bulb becomes 222 lumens when voltage at the socket drops to 11.22v. As the wiring for the brake lights has to run from battery > ignition sw > fuse panel > brake sw > connectors > back of car > bulb socket it is quite likely the voltage drop is considerable. An effective solution would be to fit a simple relay in the boot area with PVC 44/0.30 25Amp cable direct from the battery terminal (as I did with the headlight upgrade) to power the lights. A second relay could be added for sidelights as well. The relay's cost about ?4 each and the cable about a ?2.



85 - Green/Purple from brake sw
86 - Black (earth)
30 - 44/0.30 25Amp cable direct from the battery terminal
87 - Green/Purple to brake lights

For side lights (same type of relay):

85 - Red from light sw
86 - Black (earth)
30 - 44/0.30 25Amp cable direct from the battery terminal or tee'd to above relay terminal 30
87 - Red to side lights

If you are locating these relays in the boot area you should put 0.47 microfarad capacitors across contacts 30 & 87 as a spark suppressor and ensure the relay case is sealed with silicone or glue - there is always the smell of petrol in the boot of an E-Type! Alternatively you could mount the relay in the engine compartment close to the hydraulic switch and just run the 44/0.30 25Amp cable to the brake lights.

This simple mod should almost double stop/tail output from the existing setup.

Note: LED's also dim with a reduction in voltage. If you want to use an LED bulb to replace a stop bulb you need one with at least 460 lumens to equal tungsten filament. If you want brighter than tungsten you need even more lumens and the LED's must be the same colour as the lens (red in this case). Current LED's are only about 40% efficient so if the manufacturer quotes 500 lumens you get 200 lumens. To prolong the life of high output LED's they need a heatsink.