I would like to have better illumination of the gauges at night. I am considering replacing the original bulbs with LED units that have the same mounting as the original bulbs. Does anyone have any experience with using this type of lighting.

Submitted by jerry@moutons.org on Mon, 01/09/2012 - 12:36

Steve,
I installed LED bulbs from v12s.com, and got mixed results. The blue filters in my instruments (I have a 3.8, yours will be green) were bleached out or gone, so the blue LEDs they have did a great job of restoring the original color.

The bulbs I bought have several LEDs that pretty much all point forward instead of going all directions like an incandescent bulb would, and our instruments depend on scattering light off of the instrument interior, so the light was a little dimmer for that. In addition if you mount them as the incandescents and push them fully home, the LEDs are pushed up against the instrument and less scattering is possible. I found that pulling them out as far as possible gave a better light. Still, a bulb that shone light more to the sides would work better.

The voltage at the wire is often low in our old cars, and I found that cleaning all connections between battery and lights made a difference. Good idea for all the connections as this is often where dash fires start.

At the time I got mine, there were none available for the lights illuminating the switch legend strip at the bottom, but I got an adhesive strip of LEDs and wired that in, stuck on a strip of harder plastic that fit into the area, and that is quite satisfactory. In fact, it's a little brighter than the instrument bulbs.

I had had the tach and oil pressure gauges rebuilt/replaced, and so their faces are much cleaner than the other instruments, and so they are much more legible than the others, so cleaning the faces will make a difference.

The instrument dimmer switch does work and dims the instruments as before.

Overall the illumination is better than with the old incandescent bulbs, but not quite satisfactory. I would hope that the LEDs available today would be a bit brighter and so better. I'm not unhappy with the result, but I would like to be able to read the instruments very well on the dim setting, and this is not possible now.

The current required for the LEDs is a lot less than the incandescents, and so we have that little extra margin on dark nights with worrisome generator or alternators.

Some have used electroluminescent strips inside the large instruments and found that to be very good.

FWIW, you can get more answers to questions like this on the jag-lovers forums, as this is where most of the E Type experts hang out (most are JCNA members, too.)

Jerry Mouton