Part 1
Automotive lighting is my professional field. I do research and writing; regulatory, technical, and product development consulting, sales, and I serve as an answer man on the subject for various groups and associations. I am the General Editor of the automotive lighting industry technical journal.
The first issue that needs to be worked around is that the amount of junk and bad info completely overwhelms the amount of good info and good lamps on the market. All of it, junk and good stuff alike, is marketed and hyped as an "upgrade". Most of it is, at best, different but not better than the original lamps. Most of it is different and objectively
worse than the original lamps. I am not going to make a pitch for anyone to buy anything from me here; I firmly believe that the most important thing is to get proper, technically sound, factually correct information out there. Then people can make an educated decision to buy headlights from me or anyone else who sells good lights, or they can choose to disregard the facts and go buy bad ones from any of the many vendors who sell them.
So first, some education. To see well at night requires good headlamps equipped with good bulbs and fed by good wiring.
Sealed beams
There are very few decent sealed beam headlamps, and none in the 5¾" (quad round) size. All of Sylvania's and Wagner's sealed beams and most of GE's are poorly-focused junk, made on decrepit tooling that should have been scrapped and replaced several times over. The problem is there's no money in doing so; the sealed beam market is too small to make back the investment in new tooling any time soon, but too large to drop the products entirely. The way the US/Canadian regulations are written creates a loophole for makers to continue producing lamps that might have complied with the regulations when the tooling was new, but no longer comply. This may eventually be fixed when the regulation is rewritten, but for now that's how it is. The only sealed-beam headlamps worth buying are the GE Night Hawk items, and there's no Night Hawk sealed beam in the small round size. The Sylvania Xtravision "upgrade" is an out-and-out scam; they are no different at all from the regular Sylvania H5006 and H5001 small round sealed beams (the rectangular and large round Xtravision sealed beams
are different than the non-Xtravision equivalents, but are not good). And even if you buy NOS halogen sealed beams made when the tooling was still in good condition, you're not getting good headlamps. When halogen technology was introduced for headlamps in Europe in 1962, the European industry used the extra efficiency of halogen vs. regular tungsten bulbs to increase the amount of light on the road and improve beam focus. Wattage was increased slightly.
But when halogen technology was introduced for headlamps in the US in 1979, the American industry used the extra efficiency of halogen vs. regular tungsten bulbs to reduce the power draw of the headlamps, allowing them to use lower-rated switches and thinner wire to save a few pennies per car built. Headlamp performance was kept just above the legal minimum requirements on low beam. For example, the non-halogen #4000 5¾" sealed beam had a 60w low beam filament and a peak intensity of 25,000 candela. The halogen #H5006 5¾" sealed beam that replaced #4000 has a 35w low beam filament and a peak intensity of just under 18,000 candela, which is 28% less light. The light from the halogen sealed beam is somewhat less brownish, but there's a significant amount less of it. Result: still a legal headlamp (when they were being made on good tooling) but objectively not as good as before.
HID (Xenon)
There is only one legitimate Xenon headlamp in the 5¾" round size. It's the XE-5R shown
here. Some fairly substantial bucket modification (sheetmetal cutting) is required for them to fit, and they are costly, but they are made by an OE supplier. Quality, performance, and safety are all quite fine.
All the other offerings of "Xenon" headlamps in this size are junk from China and/or not as described. They are either low-quality halogen lamps with blue-glass bulbs (more info below), or low-quality halogen lamps with an "HID kit" installed or included. "HID kits" in halogen-bulb headlamps or fog/auxiliary lamps (any kit, any lamp, any vehicle no matter whether it's a car, truck, motorcycle, etc.) do not work safely or effectively, which is why they are illegal. See
here for more info on that subject.
LED
There is a set of good full-LED headlamps in the quad round size, and they're even made in America. But boy howdy, will you ever spend money for 'em (figure about $450
each)! Also, bucket mods required. They're
here.
Halogen
Most people are most likely to skip the high-dollar HID and LED options and shop for a set of halogen replaceable-bulb upgrades. Shop carefully and be skeptical; there's a ton of off-brand junk on the market, there are a lot of wrong-side-of-road headlights being brought in to appeal to the kids who drive Hondas and think anything meant for the Japanese market is obviously better, and even if you stick to the reputable brands worth buying (Hella, Bosch, Cibie, and a few others that are effectively impossible to get), there is a large range of performance among them; they're not all the same and neither are they priced alike.
H4 lamps
H4 was the world's first 2-filament halogen high/low beam headlight bulb, introduced in late 1971. Most people who think of headlight upgrades for sealed-beam cars think of H4 lamps. There are dozens (at least) of brands and lots of varieties, including ones with window-clear lenses and jewelled reflectors, blue-dot and red-dot items, tri-bar items, angel-eye units, etc. Here again, most of what is available must be rejected right out of hand if you're actually driving at night. Even if you look only at legitimate headlamps, H4 lamps (of any manufacture) in the 5¾" round size are not very efficient, because with H4 (any H4 bulb in any H4 lamp), only 55% of the total reflector and lens area is used to collect and direct the light for the low beam, because of the low beam filament shield inside the H4 bulb which is how the low beam cutoff is created. That's OK if you have a large lamp (the larger 7" round for example), but with small lamps like the quad rounds, you really can't collect much light from the bulb -- only just enough to meet the minimum requirements. Good quality H4 lamps in this size put a fair amount of light on the road surface right close to the car, which creates the feeling of "better" headlights, but they don't put enough light down the road where you
actually need it for safe driving at realistic nighttime speeds. A higher-power bulb doesn't change this; it's a limitation of small H4 lamps.
But if you don't do much night driving and need to keep the cost down, a quality pair of H4 lamps—Cibie, Bosch, or Hella are the only brands you should look at, and I list those in order of descending performance; Cibies are best—equipped with thoughtfully selected bulbs and aimed correctly, will give a broader beam coverage than the sealed beams.
If you do much night driving and/or have to contend with bad weather, get the Hella BiFocal H1 low beams, which were co-developed by Hella and BMW. They are harder to find than common H4s, and Hella doesn't officially import them to North America, so I bring them in from Germany. They're much more efficient and better focused than anybody's H4 in this size, because the
whole reflector and lens area is used to collect light, and the optics are newer and optimized to do just one job very well (low beam) rather than compromised to do two jobs (low and high beam through the same lens). Beam coverage is very broad and even, down-the-road seeing light is intense for a long seeing distance, and control of glare and stray light is very precise so when they're aimed correctly you get excellent seeing without blinding other drivers (including cops who might react extra-badly). Vastly better performance than the sealed-beam junk _and_ vastly better performance than any H4 conversion -- a substantial upgrade from the sealed beam lamps' dim, narrow tunnel of light with no side spread and excessive upward throw that causes backglare in bad weather, and likewise a substantial upgrade from the H4 lamps' relatively meager beam performance.
High beams are easy; use parabolic H1 units. Cibie makes the best ones; Bosch and Hella are OK. Even if you decide to use H4 lamps, don't use H4s in all four buckets. The high beam mode of an H4 lamp (or a high/low sealed beam) provides close-range width and fill light; the distance reach on high beam is provided by the dedicated high beam unit.
