I researched this question on the Internet including the excellent site
associated with Daniel Stern. There is nothing >legal< available that
will improve the performance of 9005 high beam bulbs. The extra cost
extreme white sort of bulbs will actually supply fewer lumens and have a
shorter life expectancy (though they do look "cool").
http://www.overboost.com/story.asp?id=102
There is additional output available for the 9006 Xtravision, but 1030
lumens as opposed to the standard 1000 lumens is not worth the drive to
Pep Boys.
http://lighting.mbz.org/tech/bulbs/bulb_types/bulb_types.html
I would agree in principle with the lumens except for one issue. The
human eye does not absorb all colors equally. I can tell you from
personal experience that color of the light DRAMATICALLY affects
visibility. I used to live on the USS Harry S. Truman, and they used
sodium-arc lamps at night because the yellow light would not be as
visible far away, so they could use roughly the same amount of lumens
as the sun gave in the daytime in the hangar bay. You still couldn't
see a thing, it was all washed out and things would fade into the
background. The human eye sees contrast better with light similar in
characteristics to sunlight on overcast days, which in the 6500-8500
Kelvin range. Most headlights are in the 3200K area, with the HID's
being in the 4100K range. The closer to overcast sunlight you can get,
the better you will see, but unfortunately modern technology hasn't
gotten there yet. So, as you can see, lumens is just the tip of the
iceburg. Check out some of the photography sites to see what I mean.
Remember, even though the DIRECT measurement of the headlight might be
at maximum when using a "human eye based" photodetector, that does NOT
mean that the REFLECTED light is at maximum!!!!
http://www.photo.net/photo/edscott/cf000030.htm
Nate