I drive a 2005 LX 4 dr 4cyl. I want to replace my headlights with HID but I can't figure out what 4000K, 5000K, 6000K...etc. means. Does it have to do with the amount of illumination? If so is the rating higher number/higher illum or lower number/higher illum? Also I have seen tons of conversion kits online but I want to buy prefabricated if possible. Any help is appreciated.

 

Most of the people here buy theirs from ddmtuning.com have unbeatable prices and very high quality. the 5000k 6000k etc does relate to the illumination, but it also relates to the color. 12000k is purple and gives off very little light, 5000k is almost pure white, 3000k is yellow. So a general rule is the lower the number the brighter it is, but it also depends what color you want.

 

The 5000K should refer to the color only. Brightness is a separate thing, really. You can probably find some good material about "color temperature" by googling that & looking for hits that are about photography.

http://en.wikipedia.org/wiki/Color_temperature
There's a color diagram in there. Look at the curved line across the middle called the "Planckian locus" which shows you the color associated with those temperatures.

5800-6000 kelvins is the color of sunlight. Which appears to be really blue, because at night your eyes are accustomed to artificial light which is mostly 3000-4000 kelvins.

 

how do i know which kind of bulb i get? like which size. i want the color to be a little blueish

 

Try reading the few post's above your post again...