Halogen draw vs. stock headlights

[patrickdotryan]

Hi all,

I've read a lot of posts that say newer Halogen headlights draw too much current for the headlight harness and/or headlight switch. But there's a lot of variation in Halogens. I have an headlight burned out. I have a spare basic Sylvania H6204 halogen that I would like to use as a replacement. The specs of this H6204 are:

Low beam - 40W (12.8V x 3.12A)
High beam - 60W (12.8V x 4.7A)

I DO NOT WANT TO HAVE BRIGHTER HEADLIGHTS AND DONT WANT TO UPGRADE MY HARNESS OR SWITCH OR ADD A RELAY. I JUST WANT TO REPLICATE THE STOCK SETUP.

My questions are:

1. what were the equivalent specs of the stock headlights? We're the specs SO different from the above? Given the constant of 12.8V, how much lower was the wattage on the originals that these halogens draw more than the stock setup?

2. Does anyone know the model number of the original set up (6104 like Mustangs? not sealed beam?)

Thanks.
Patrick

[Ranchero50]

I'm running the Sylvania XTRAvision H6024 60/40 and it's comparable to the '68 Ford Script lamps I had in it. OEM were slightly more yellow and had a more coarse blotchyness at the exrtreme sides. The H6024's are slightly whiter, project further with a finer light on the sides. I paid less for them than some crappy H4 modules that poorly projected a horrible blue tinted light.

I checked the voltage drop across the lamp and it was the same as the OEM, less than .25 volts different from the battery terminal. If you have a higher voltage drop you need to figure it out as it means you have resistance through the circuit and that will suck the brightness out of the lamp.

[Nitekruizer]

I remember seeing some of the old 7" round sealed beams with wattages stamped on them. I remember seeing 55/65 Watts stamped on the back of the sealed beam bulbs. I'm assuming that they were 55 Watts on Low and 65 Watts on High. Some of the later non-halogens may have been 60/60 also, if memory serves me correctly. In any case, the Halogen 6024 will be brighter, especially on High, because a 60 Watt Halogen will produce a lot more light than a 60 or 65 Watt incandescent. The nice thing is that it will use the same amount of current.

If the Low beam portion of the Halogen sealed beams are 40 Watts and if the Low beam portion of the old incandescent sealed beams were 55 Watts, then the Halogen Low beams would actually use less current while providing the same or even slightly more light. If you still have a working incandescent sealed beam, you could measure it's resistance with an ohmmeter and compare the reading to the resistance of a Halogen sealed beam. The bulb with the highest resistance will consume the least current.

[patrickdotryan]

Thanks Ranchero and Nitekruizer.

To clarify I'm talking about the basic Sylvania H6024 40W/60W sealed beam and based on all the comments it appears they will not add any drain compared to stock.

I think that the H6024 XV (xtravision) that Ranchero is talking about are rated at 53W/63W and if so there is more draw on both beam settings compared to the basic H6204 sealed beam halogen that I have.

What we don't know for sure is how either compares exactly against stock. For future searchers of his topic it would be great if someone could confirm what the stock headlight wattages were because I couldn't find it.

Thanks again. Patrick

[Ranchero50]

Partrick, play with this formula to gain a better idea. For any given wattage of bulb, the voltage at the bulb changes the watts measured. Google may help you find out how bulbs are rated (It's going to be a specified voltage across the terminals. Wattage is just Amps of current X volts.

http://www.sengpielaudio.com/calculator-ohm.htm

I don't see any voltage difference with the lights on. I do have the upgraded Dodge alternator on my 6bt being controlled by a stock Ford electronic regulator. But even a 60 A Ford alternator should drive these lamps with ease as long as the wiring and switches are healthy. Often water will get to the high beam switch and cause it to draw higher amps (see if it's warm after running for a while with the lamps on).