Headlight bulb filaments - which is which?

[Sparky]

I recently picked up a pair of Model A headlight assemblies to replace my current sealed beam units. I had to rewire the sockets, and the bulbs were missing so I ordered a set from a parts supplier. The bulbs I got have two filaments; one is straight and the other is bent in a V-shape. Which is high beam and which is low? And the low beam filament goes on top, correct?

[columbiA]

If your bulbs are 32-50 CP,then the brightest beam should be the lower filament.If 32-32,s it wont matter which way it goes as long as the low beam is the upper filament.

[KGBnut]

I had the exact same problem and found it surprisingly hard to find the correct answer, in part, because those bulbs can change depending on the supplier. You would think they would be labeled.

If you look at those bulbs from the side, one filament will be dead center, the other will be slightly off-set. The one in the center is the brighter high-beam. You can also grab an amp meter, wire them up to a battery' and see which draws more current, again the brighter high-beam. I'm 90% sure it is the V-shaped filament. Later today, I will double-check and get back to you.

Once I figured it, I made damn sure to label all my spares with "TOP" written on the base of each bulb.

Ken

[Sparky]

Yeah, I assumed the V was the high beam also. I hooked them up and judging from the light pattern on my garage wall it seems correct.

[KGBnut]

Yes, I just got back from the garage. I double-checked and I was correct. The V is, in fact, the high-beam filament. Remember, the bulb should be installed with the LOW-beam filament on top.

[Sparky]

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Thanks!

[sturgis 39]

Originally Posted by Sparky

Thanks!

Thanks from me too.

[insomniacshotrods]

Ok so the off set filament is low beam and it goes to the top when seated in socket correct? Cant see much of a V shape on mine but if bright is the centered one mine was upside down. So thanks lights look better now.

[700rpm]

The reason I like the Ford Barn so much is I learn something almost every time I read it.

[Mike V. Florida]

Maybe this will help. The center filament reflects evenly in the reflector.
The upper filament hits the reflector at a different, higher angle and the light bounces off and points down.

[larrys40]

Hate to tell you all but the reproduction bulbs are junk. The fillaments should v shaped on both, high and low beam. Take a look at an original GE1000 bulb... and you will see what I mean. They are both V shaped and will focus. The flat filament won't produce the beam of light and thus directed off the reflectors and out in a beam through the lenses. The repro flat filaments are just that... they produce light but won't focus a beam of light projected outward.

Of course focus the headlights based on the service bulletins
32/50 would be the same.... v shaped
Larry Shepard
St. Charles, MO

[rscardina]

I realize this is an old thread, however, I have a question that applies. I converted from sealed beam headlights to the repro original style headlights. The new repro bulbs that I bought are dual element bulb both v-shaped elements. I am assuming that the more centrally located element is the high beam and should be located on the bottom when installed and the offset element is the low beam and should be located on the top when installed. Is this assumption correct or is there something else I should know?

[Mike V. Florida]

This may help;