I have the gauge cluster on the bench and so upgraded to the 4 Watt Osram bulbs and was okay with the results. So I experimented with several LEDs ba9s bulbs. LEDs have many varieties; forward emitting, with 30/90/120 degree beams, there are side emitting with various LED quantities (=lumens), and then there are multiple temperatures of white color and then also red, green and blue LEDS. I bought them all!
I have settled on going with LEDs in the VDO gauges because; they are brighter, I mixed two types to get better brightness consistency across the 4 gauges, no heat at all and also the current consumption was a fraction of the 4W incandescent. The Osram 4W are 35 lumens over a hemispherical pattern (so maybe 5 lumens up, down, left, right and forward?).
After trying a variety here is what I like –
The backlighting in the clock, speedo and tachometer are all like cove lighting – shining from behind and around the gauge face and then onto the black ring you see just behind the glass which is a white reflector on the ring’s backside and that results in light on the gauge faces. Where the light doesn’t get to the reflector the gauge face will look a bit dim. Also the speedo uses two bulbs to light the reflector while the tach uses one on its top and the clock uses one on its bottom – so maybe that the reason my lights were inconsistent across the gauges.
My speedo and tach now have 60 lumen 4 LED 2-way side emitting bulbs (a beam to the left and to the right so to speak). Twisting the bulb socket you align the beams to be locally tangent to the circular housing and reflector ring for peak reflection and brightness. So the beam direction for the speedo’s side(s) mounted LEDs will be vertical and for the tach’s top mounted LEDs align the beam to be horizontal – twist it off tangent if you want less brightness. https://www.pilotlights.net/ba9s-bayonet-type-bulb-side-emitter-12v-24v-super-bright
The fuel/temp gauge lighting does not use the full circular approach and instead a lesser cove window for each of the two gauges. I now have settled on the 60 lumen 4 LED 2-way side emitting bulbs. https://www.pilotlights.net/ba9s-bayonet-type-bulb-side-emitter-12v-24v-super-bright
My clock, with bottom bulb, was more challenging than the tach to get consistent light around the full gauge face, not sure why. So I used a 90 lumen 5 LED 4-way side emitting bulb and it’s now better and more consistent with the other gauges. https://www.superbrightleds.com/ba9...wer-ba9s-bulb+color-warm~2700k+packamt-single
The above are all warm white in color.
For the red green and blue telltale lights I again used the forward emitting bulb putting 12 lumen 1 LED in a 90 degree forward beam, in warm white. There is color film in the gauge face.
I have settled on going with LEDs in the VDO gauges because; they are brighter, I mixed two types to get better brightness consistency across the 4 gauges, no heat at all and also the current consumption was a fraction of the 4W incandescent. The Osram 4W are 35 lumens over a hemispherical pattern (so maybe 5 lumens up, down, left, right and forward?).
After trying a variety here is what I like –
The backlighting in the clock, speedo and tachometer are all like cove lighting – shining from behind and around the gauge face and then onto the black ring you see just behind the glass which is a white reflector on the ring’s backside and that results in light on the gauge faces. Where the light doesn’t get to the reflector the gauge face will look a bit dim. Also the speedo uses two bulbs to light the reflector while the tach uses one on its top and the clock uses one on its bottom – so maybe that the reason my lights were inconsistent across the gauges.
My speedo and tach now have 60 lumen 4 LED 2-way side emitting bulbs (a beam to the left and to the right so to speak). Twisting the bulb socket you align the beams to be locally tangent to the circular housing and reflector ring for peak reflection and brightness. So the beam direction for the speedo’s side(s) mounted LEDs will be vertical and for the tach’s top mounted LEDs align the beam to be horizontal – twist it off tangent if you want less brightness. https://www.pilotlights.net/ba9s-bayonet-type-bulb-side-emitter-12v-24v-super-bright
The fuel/temp gauge lighting does not use the full circular approach and instead a lesser cove window for each of the two gauges. I now have settled on the 60 lumen 4 LED 2-way side emitting bulbs. https://www.pilotlights.net/ba9s-bayonet-type-bulb-side-emitter-12v-24v-super-bright
My clock, with bottom bulb, was more challenging than the tach to get consistent light around the full gauge face, not sure why. So I used a 90 lumen 5 LED 4-way side emitting bulb and it’s now better and more consistent with the other gauges. https://www.superbrightleds.com/ba9...wer-ba9s-bulb+color-warm~2700k+packamt-single
The above are all warm white in color.
For the red green and blue telltale lights I again used the forward emitting bulb putting 12 lumen 1 LED in a 90 degree forward beam, in warm white. There is color film in the gauge face.
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