LED 7" Round Headlamp Update
For a sealed beam, halogen sealed beam or an H4 type lamp, current draw depended on the specifics. They are designed to work at approximately 14 volts.
The design voltage for all automotive lamps in the US and Canadian regulations is 12.8v. Lifespan testing (not regulated; it's purely for commercial purposes) is done at 14.0v because that makes the testing easier (takes less time) and represents a worst-case scenario (vehicle with hyperactive voltage regulator temperature compensation, operated in very cold weather).
the out of production Nighthawks, H6024 low beams are rated as 35 Watts. So they draw less current than either 6012 or 6014 lamps on low beam while supposedly meeting the same lighting standard.
Yes, but that doesn't mean equal performance. The lighting standard in question allows a
giant range of performance; that is, every test point that makes up the beam pattern definition has a huge allowable range of intensities. The range is too big at some of them, for a really dumb eye-roller of a reason, which is why useless headlamps and high-glare headlamps are out there on the roads along with effective headlamps and low-glare headlamps.
The really stupid reason: the relevant US regulatory agency, NHTSA, occasionally adjusts the lighting regulation to allow higher performance (whatever that might mean for the specific question at hand—better seeing, less glare, amber rear turn signals instead of red ones, etc), but almost never adjusts the regulation to
require better performance (minimum acceptable low beam performance and max allowable high beam performance haven't changed since 1978, for example) because they feel that doing so would imply the previous requirements were inadequate, which might expose the agency to neglect-of-duty lawsuits.
A-bodies through '72 came with 6012 headlamps.
This Wagner catalog lists them as 40/50 Watt.
Well, 50/40 (high/low beam). And then, as you say, came the 60/50w 6014. And then along came Ford and Sylvania, who together over the years foisted an enormous amount of poor lighting onto US drivers. Unlike the Yurpeens who, in 1962, went "Hey, neat, halogen technology gives more lumens per watt, so we can give drivers a whole lot more light to see at night!", the Americans in the late 1970s (having spent 15 years going "Haw haw haw, stupid Yurpeens can't quit messing around with their headlamps; they should just use our sealed beams which are obvs superior", went "Well, fine, yeah, halogen technology gives more lumens per watt, so we can reduce the headlamp wattage and specify thinner wires and cheaper switches, while still meeting the minimum requirements". Then they straightfacedly claimed this was a great idea in the public interest because lower-wattage headlamps would save fuel. Yes, Ford really argued that the 9 mpg of a '79 Lincoln Town Car with a 460 V8 would improve with 35w versus 50w low beams. (What would it change to? Oh, y'know, 9.000000000001 mpg).
Result: the halogen H6024 with 35-watt low beam gave a peak intensity of about 20,000 candela, versus the non-halogen 6014 with 50-watt low beam, which gave about 26,000 candela. The low beam of the quad round system skidded even worse.
Our cars have a long current path to the headlamp. Its not just age. The final leg of the headlight circuit in A-bodies is 18 gage wire. A relay harness takes the load off that 18 gage wire, shortens the path, and reduces the load at the alternator's bulkhead connection.
All true and correct. More geeky details about it
here.
(Speaking of
geeky details about sealed beam headlamps…)
