Instrument panel bulbs (194 vs 168). What do ya think?

All my wires are excellent and have new regulator on back of instrument panel, also new switch and 194 bulbs installed. I just wish the the gauges were a little bit brighter. I did some research and the specs for the 194 bulb , which is factory spec, is 3.78 watts and 25 lumens. The 168 miniature bulb is the same size as the 194 but is 4.9 watts and 38 lumens. So the 168 pulls 30% more power than the 194 or 1.1 watts more. I think the 168 would be sufficiently bright. Any one think there would be any issues with using the 168 over the 194? 1.1 watts should not make a lot of difference I would think as far as heat on the circuit board or in the blue domes in the panel. Just don’t want to use LED, not real fond of the clock with quartz movement coming and I still use points, just want to keep it close to original and era as possible.

FWIW I have spent the last three years developing reproduction dash panels and part of that is recreating the little green lenses that are in front of the turn signal lamp. All the original ones are slightly burnt in the center. That tells me that the original bulbs were as hot as could be. For this reason I would strongly suggest using LED Bulbs. If the color temperature is similar you should have the same color and a lot less heat

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I’ve wanted to do the same, but seeing how brittle and burned the plastic is already, I decided to stick with the original bulbs. That extra 1.1 watts is 30% more power in a tiny space surrounded by old plastic. I’m like you in wanting to stay original, so haven’t gone to LED’s either. But yeah, the gauges are pretty dim and I probably should consider LED’s just to limit further damage.

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The LED bulbs are fantastic. No drawbacks and brighter.

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My initial try with LEDs turned out too bright and had no response to the dimmer (to little current draw for the rheostat to affect it). What are people using that has appropriate brightness and adjusts with the standard dimmer? I ended up building a separate resister box to drop the voltage to the LEDs and also add load to the dimmer rheostat. Apparently, there are simpler ways.

It may depend on the LEDs. I used the hipo kit from WCCC. I left the original lamp in the radio and the dimmer worked.

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The WCCC LEDs must have some internal resistors in series to pull enough current to get sufficient voltage drop, and are set up to have an appropriate brightness. If I have to revisit my dash lights, it sounds like the way to go.

I try to keep it simple and original or era, so I just won’t do any LED mod. And the other poster stated the 194 is more than hot enough for the blue plastic domes, so will stick with the original bulbs.

Most LED bulbs have a very narrow voltage range for dimming - that’s why the light switch rheostat works so poorly with LEDs. It goes from all on to all off over a short angle of rotation.
The best way to dim LED bulbs is to use a PWM (pulse width modulated) circuit that rapidly switches the LED On/Off. Your eye/brain averages the light received as bright/dim.
Years ago, Cleve @ WCCC asked me to design a dimmer but cancelled the project.
It is a plug-in module that uses the factory rheostat to control the PWM circuit.

I found that the automatic console shifter lamp and the radio lamp were unable to be replaced by LED’s so those two lamps also provided the voltage drop needed for dimming.

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So Royce, do the LEDs in your gauges dim adequately along with the standard bulbs in your radio and console? Color looks about right? If so, I’m ordering a set of those too.

Yep it works like the stock bulbs but markedly brighter.

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I installed an LED on my stock AM radio on my 67 with no issues.