Found these on ebay. Interesting...The author is Zeoth
Purpose: Understanding and purchasing HID (High Intensity Discharge) technology for your car.
Question: Everyone has been awed by the infusion of those blue headlights found on some popular high end model cars such as BMW, Lexus, Audi, and Mercedes. The question is: How do you get them for your car?
Background: Unlike the popular belief, Thomas Edision didn't develop the light bulb, but he developed a PRACTICAL incandescent light. There's three types of headlight technologies: Halogen, HID and LED (LED we'll leave out for now)
Everyone should know what standard halogen bulbs are. These are the common bulbs that Edison made famous. There are multiple issues with these bulbs. First, they are only allowed to be so bright as to prevent blinding other drivers. Second is their beam pattern. Light is scattered and not really focused on the road in front. Finally is lifespan. Bulbs burn out frequently because they are still filament based.
Then there’s HID (High Intensity Discharge) technology. People has called them Xenon as well but that just refers to the gas they are using. We normally see HID lamps in the form of mercury vapor and sodium vapor lights used as street lamps and as outdoor lighting for stadiums. These lamps are popular because they are efficient. In the case of sodium vapor, they are twice as efficient as normal fluorescent bulbs. The problem with that technology is that there is a long startup time for mercury vapors. Xenon helps solve the start-up problem, as does a special controller (ballast). HID solves the problem of bulb lifespan but what about beam pattern and making the light brighter? I’ll get to that after some more history lesson.
HID technology was introduced to Northern America cars starting with the 1995 Lincoln Mark VIII. Then other automotive dealers such as Audi, Mercedes, and BMW started putting them in their cars as well. Being rare and cool looking, 3rd party companies jumped on the bandwagon and started developing “HID like” bulbs which they market as HID bulbs, Euro Spec bulbs, or Plasma Blue bulbs. Those are nothing more than painted halogen bulbs that you now can find on eBay for $10. These bulbs do nothing more than change the color coming out of the headlight to blue. This blue light is dimmer, tiring on the eyes, and having a shorter life span than the stock halogen bulbs that came with the car. Though mostly not illegal (DOT certified), it’s a highly dangerous thing to do.
So the next step is to put the HID technology into the existing headlight. This is what is commonly referred to as an HID kit ($500). The HID bulb and ballast (the HID bulb control box) replaces the halogen bulb and thus in effect putting a very bright HID bulb into a halogen housing (stock headlight housing). This achieves the brightness of using HID but the beam pattern is scattered like a halogen bulb because the housing is not meant for such a light source. In California the use of these HID kits are illegal because they are not focused and glare other drivers (Hence not DOT approved). DOT = Department of Transportation.
HID kits come in different color and are based on the light temperature. The higher Kelvin the light color, the bluer the output becomes. Kits advertising 8,000k and above are so blue that people have a hard time distinguishing between your car and an ambulance or police car. In contrast, all cars equipped with HID as standard equipment comes with 4100K bulbs. Also HID Kits using OEM ballasts such as those made by Hella or Philips are the best. They are more likely to last longer and has additional safety features built in that may not be available on “Home made” kits. Also the glass part of the halogen bulb is replaced with the glass part of the HID bulb. That’s how the bulb fits into the stock headlight housing. This glass swap is commonly known as a rebased bulb.
So finally what separates the real HID technology and the fake, is the addition of the HID projector (some actually reflector style HID but those aren’t very good and you can’t install these in your car). It is the lense and shield of the projector that concentrates the beam to the floor and creates a cutoff above a certain height as to not blind other drivers. At the cutoff there is a blue color due to the light spectrum. In most cases the color is either blue or purple. The popular trend now is to take the entire HID technology (HID bulb, ballast, lense and shield) and put them into the halogen housing. This is referred to as a HID retrofit ($1,000+).
If you notice, there are even differences in HID lense technology. Some are brighter than others. Some are bluer than others. Some are more blinding than others. The current cars with the best projectors are off Honda S2000, 2004+ Acura TL and 2003+Acura TSX which uses the powerful Stanley/Kioto projectors. Valeo are the next best which are usually found on Audis and then finally there is Bosch.
Recommendation for HID Kit components:
1) Rebased Philips bulbs (4100k is the brightest but also yellow looking. 6000k is white looking. 7300k is a very crystal blue looking)
2) Hella or Philips generation 3 or 4 ballasts
3) Buy or build yourself a wire harness to power the ballast from the battery with the headlight harness used as a constant source switch.
Recommendation for retrofit components:
1) Cars with H4 high and low beam in a single bulb should use the Acura TL bi-Xenon projectors (which mimics having high and low beam in one projector). Otherwise use the S2000 or the TSX projectors.
2) Use D2S 4100k or 4300k bulbs made by Philips.
3) Use Hella or Philips generation 3 or generation 4 ballast.
4) Buy or build yourself a wire harness to power the ballast from the battery with the headlight harness used as a constant source switch.
Zeoth - Friends Don’t Let Friends Drive Stock
Guide ID: 10000000000007982Guide created: 10/03/05 (updated 04/30/08)