halogen bulb conversion

[rdssdi]

Trying to wire H4 lamp conversion.

Is the "main" beam the same as "high" beam in the U.S.?

Which filament is energized when the "main" beam is selected? The filament with or the filament without the reflector.

Bob

[GrUmPyBoDgEr]

Maybe I'm missing something here but when I changed my car from the original "sealed beam" units to more modern 7" reflectors for H4 lamps the original wiring socket fitted directly onto the H4 lamp "prongs"
"Plug & play" so to say.

I would think that "high" & "main" beams would be the same, just a different language,

Cheers
John

[rdssdi]

I am rewiring the lighting in its entirety. Including new plugs.

Also the new conversion lamp assemblies are not piloted. I know the bulb is to be in only one position. I have determined that the reflector / filament is the dip or low beam. It is to be pointed upwards and the light will be reflected off the top of the main reflector directing the beam downwards towards the road. Without the bulb position being registered that will not be the case.

I will inspect it further and take some photos.

Bob

[rdssdi]

Here is a photo of the part. It came in a lucas box "LUB319". It had a halogen H4 in it but that cannot be correct as the unit is not piloted. Anyone recognize this part?

[mikealdren]

Not sure what car you have Bob but the headlamp connection did change in the early 1970s (or maybe late 60s) to the familiar 3 pin design, before that IIRC they used spring loaded contacts - I had to use a converter on my Vauxhall Viva to take the 3 pin design.

Yes, main beam is what you would know as high beam. The H4 bulb has two filaments for dipped and main beam and the reflector and lens on the light should allow them to both work correctly., adjust the dipped beam to just below horizontal or use a beam aligner.

However, not sure what you mean by piloted - do you mean an aperture for the 'sidelight' or 'parking light'? Looking at your photo again, is it missing the clips to locate the bulb and is that what you mean by piloted? The bulb holder shoudl register the bulb in exactly the correct position.

Mike

[rdssdi]

Piloted on an H4 bulb is the three tabs that align the bulb in the housing.

The housing I have, I believe, are for P45t based bulbs. The P45t R2 is the halogen version. In order to move on with the installation I have purchased Hella halogen conversion units. (Sealed beam to H4)

They use the H4 bulbs and are high quality units.

The Lucas housings I have are also very good quality but I could not find the P45t R2 bulbs and I was tired of looking.

It is also possible that there is an adapter for the Lucas housings that will register with the P45t unit and accept the three prong H4 bulbs.

Bob