Topic: 65 Bulbs ?

[Brian Conway]

Correct bulbs for my instrument cluster #1895 ?  These say they a 12 volt 4 watt.  The part number is correct but I don't know about the Watts ?  Thanks,  Brian

[jwc66k]

The "watts" is power used. It's a function of voltage and current. Wattage can be converted to "lumens" which is the amount of light the bulb will produce. Will the bulb work in your instrument cluster? Yup.
Jim

[Brian Conway]

Thank you Jim for the information and confirmation.  I am not fluent in ' automotive electric ' and would not want to over whelm the 12 volt fused system in my car.  The on line conversion tables don't make it easy to convert the assorted lighting terms to actual brightness.  Brian

[rodster]

If the part number is correct you are good to go.  Specs for a bulb are specific to that part number.

[jwc66k]

' automotive electric '

Think "home electric" - a 100W bulb is brighter than a 60W, bulb both of which are rated at 120V. The same approach can be used in a stove's heating element, 1000W is hotter than 500W. The formula is easy - P=IE (or PIE) - Power equals Current (I) times Voltage (E). You can calculate current with this variation - I=P/E. The current draw can tell you wire size. It's not rocket science, but it's a start.
I mentioned "lumens". There is a relationship to power but I'm too lazy to drag out my old engineering books to look it up. The PIE formula was learned in the US Navy back in the late 50's. When I related this formula in a electrical engineering class, the professor was astounded as to how simple it was, and - "How could the Navy teach this". His was an academic world, mine was real.
Jim

[5F08KGT]

-Ever think of switching to LEDs?

[jwc66k]

-Ever think of switching to LEDs?

Not very "concourse" are they.
Just for the record, I've not had to replace any of the 1895 bulbs on any of the several 65 and 66 Mustangs I've owned. They are very reliable, but they do burn out. The only miniature bulb I've had to replace in any of my Mustangs was in the one in the radio, an 1891. To do this requires the radio to be disassembled. I have had to replace exterior bulbs.
Jim