While my experience with Xenon bulbs is rather limited, I haven't noted any reduction in heating effects in my 5-cell Mag-Lite flashlight powered by 9000 mAh NiMH 'D' cells compared to halogen bulbs, or conventional Tungsten bulbs, either! The reflector head still heats up significantly after 30 minutes or more of continuous operation!

Either 5 Watt or 4 Watt bulbs are still too much of a load increase for the dimmer rheostat in the headlamp switch! I suggest the following circuit:

http://forums.pelicanparts.com/uploa...1163728739.jpg

Are you sure something isn't wrong with your stock instrument lighting systems?

Some of those pictures look very dim. Like the bulbs aren't working right, or some are burned out.

The stock bulbs on my '88 are very bright. I usually turn them down a bit, I can't imagine anyone would want them any brighter than they are when they are at full blast, at least the ones on my car.

Warren- What program did you use to draw that circuit?

Thanks,
Skip

Subscribing. Interesting thread guys...

Warren, I agree that a relay would be needed to isolate all the instrument bulbs if they are converted to 5W bulbs. The circuit you show is great and I think this is the way to go if I upgrade.

One question on your circuit, would you pick the 30Amp relay from the reostat? I would think you would not, it would be better to eliminate the stock reostat and pick the relay from a line on the headlight switch that goes HOT once the switch is pulled. Maybe the parking light circuit. The rest of the circuit makes most sense to me. Thanks for taking the time to post this picture.

Yes your observations are correct, my stock bulbs are old. But I do have a new one for the clock and have put it in the dash and still would like a little extra light. I have ordered 10 new BA7S stock bulbs and will update the left half of the dash with stock new bulbs (Tach and all gauges to the left in new stock bulbs) and then I plan to update the Speedo and the clock with the retrofit 5W bulb approach so really have a side by side comparison. I will also power the entire dash all gauges with 14V from my external HP power supply. Once I do this we will have solid foundation for knowing just how much better we can get our gauges lit. I agree with you that for many folks just changing you old bulbs may be the solution. But for me as I get older my eyes seem to get worse. I'm just testing diffrent ideas. I actually think this project will be succesfull and very cheap to do. If I go with 194 bulbs they are about $1.00 each at you local auto store. Also, I found 168 bulbs are the same size as 194 bulbs but not as bright and may also perform well, need to put current clamp on them to see what the draw is but I'm guessing 168 bulbs are 3watts.

I have always said, don't jump to this modification without first replacing your stock bulbs! For many folks this may be all you need to do to be happy.

Sal,

The relay only draws 155 mA, so it seems logical to use the available Blue/Black instrument wire, rather than try to run another wire to the light switch.

Skip,

I used Irfanview to capture screenshots from the Velleman manual and an earlier thread on headlamp relays ... pasted together, changed wire colors, erased extraneous leads & labels, and labeled with Microsoft Paint.

OK, I have been taking lots of pictures and have many photos to share. Pics of howto prep 194 bulbs so they fit in the gauges and other pics I have as I work on this project. I know folks here want to see them but here is the problem: I don't think cluttering this forum with scattered pictures is the right way to post them. So I have a few choices on howto share this info (By the way I'm a EE and Software Engineer so the web is my life). Here goes:

1. just document everthing in a Word Doc and post it on my web page.
2. same as above but in PDF format
3. Post all my work on a standard web page on my site (HTML).

The first 2 are really the same I can create a PDF from the Word Doc in about 30seconds. So the real question is how do most people like to see this project documented? My vote is Word Doc - I like this because you can download it and it's easy to print just what you want.

Please chime in and let me know what you folks think.

Warren, OK I buy it, using the current Reostat output is SIMPLE! This is very easy simple approach and keeps the wiring down to a minimum. Just thought I'd ask, was afraid that if you turned the reostat down the relay might not pick and someone would be left wondering what happened to the lighting. I think your educated guess here is correct and the relay would pick no matter what.

Thanks for the clarification.

Sal,

I think PDF is the way to go ... it prints just as easily as Word, and comes much closer to WYSIWYG than Word or Internet Explorer have ever been since the days of Windows 3.0 in 1990!

Sal, between choices 1 thru 3, I say you choose what's easiest for you. We'll all appreciate the info, regarless of how you package it. :)

Ditto the above, but please note that some people do not like PDF files as you can't copy bits from them.

PS - just for clarity, the relay upgrade is the "Sucro" relays which I believe direct curren directly from the battery through the headlight & dash circuits - but I could be wrong

Holy moly, I feel like a kid in the candy store for the first time.......to think I will actually solve the problem of weak dashlights is great :)

I am glued to this forum, thanks everyone for your work.

I don't think I will need to print it, just have a good look and go do it. So I like posting it on a web paige.

Page.
My little girl is Paige

Here is a first draft of the Word Doc I'm putting together on howto improve your gauge lighting. It's a work in progress and I'll just keep adding to the doc and updating it as time goes by. You can get this early doc from here:
http://members.cox.net/widebody/GaugeLighting/911GaugeLightMod.doc

Or try this link:
http://members.cox.net/widebody


Lots of picture in this doc and many more to come.

Few other things I have learned: the stock 194 bulbs are not 5Watt they are 3.8Watt and draw about .3Amps. I thought they where 5watts but that was an wiered 194 bulb I bought at Walmart that was marked as a Xenon bulb 5W.

Sal, I think your link is not quite there...

WOW you are fast, try it now

That looks better... I think. I do not have word on the pc I am at right now, but at least it opens the link and asks if I want to open in Word. So I think link is now good.

Can't wait to look it over...

Shane

Sal, I really like the write up. I don't have the wiring schematic in front of me but here is a thought..maybe Warren will jump in. Why not trigger the the relay from the parking light terminal on the OEM light switch. You could grab this connection from the switch or the fuse panel. For those of use that never need the dimmer we could omit the K8004.
I'm also wondering if the OEM dimmer can be used with K8004 in place of the external pot?