fantastic thread, I just got done reading through the entire thing. Quick NOOB question for you.
How do projectors compare to stock halogens in terms of reliability in the offroad world? I'm concerned about vibrations, extreme moisture (river crossings), dust/dand, extreme temperatures, etc. Do you think halogens or projectors have the edge in the longevity/reliability category?
Thanks! Not noob at all... I'll try and give you an answer:
A HID bulb has an average lifespan of approx 2500 hrs. A halogen bulb has a lifespan of
up to 500. Keep in mind this is an average and, like anything, will vary with different quality levels of the components - or bulbs actually being used.
In my personal HID experience, I have wheeled my truck quite a bit with HID's and I have never had any failures due to vibrations, or heard of any for that matter. I mean theoretically it could happen if the electrode chamber were to receive a crack from a hard enough impact - but at that point you'd probably be replacing more than just bulbs... more like a front end collision! The projector bodies themselves would not see any ill effects from vibrations as they are a single body of metal with a glass lens. As long as a they have been retrofitted properly and attached to the new housing securely (speaking in terms of a retrofit here, not an OEM projector equipped headlight assembly).
Moisture could produce a problem, like with any electrical component, but most of the quality HID ballasts are weather sealed. In this regard even OEM Toyota Kioto ballasts are not as weather sealed as the Morimoto units that I use for retrofits. The Morimoto units have an externally sealed casing and the internals are coated with a rubber filler/sealant. I have had mine underwater briefly and they still work great!
As long as the headlamp is sealed accordingly, you should not really have any issues with dust/sand migrating into the headlight chamber. The only exception I see to this is if you are CONSTANTLY in a desert/sandy environment. All headlights have small "breather" holes to assist in fog reduction and rapid temperature changes. These are usually located on the backside of the headlamp and are out of the way of dust and sand, but with absolute prolonged use in a dusty environment, there is a chance of dust penetration. This would be the case for any headlight, both HID or Halogen.
HID's are more efficient and last longer than a halogen setup. Their downside being a higher cost of adoption and there are more physical components to an HID setup vs. a halogen one. The greater amount of components does increase the potential for fail points. However HID's have come a long ways and have been around for a long time. If you are using quality components, an HID system is a hands-down winner.
For more in-depth information regarding all of the HID components, this is a very useful source:
Helpful information on upgrading headlights from The Retrofit Source Inc
I hope I have answered your questions in my ramble...
