iambeetle

Okay... I am really new to cars... if I sound like an idiot... please forgive me and forget that I ever post something stupid like this...

I want to ask....

I think my headlight is not bright enough... so... I am thinking about to make it brighter...
I heard that A4 already uses HID headlight... so... should I just change the light bulb to a brighter one?
I noticed that there are several types of light bulb, like.. 4500K, 6000K, 8000K and so on... are the differences just the colors? or also the brightness..?

I kind of heard that a brighter HID needs higher power for it, does it mean that if I want a brighter HID, i need a new HID system?

Any good websites for shopping and learning stuffs about HIDs?

wow that's a lot of question...
I am really glad if anyone can help.... thanks a lot!

Black_RS4

What year is your A4?

akula-ssh

A4's come in either halogens or xenons; the latter is HID in automotive speak. I'm guessing you probably don't have xenons if you think your headlights are dim; as a check, are you headlights more yellow than white? If so, you've got halogens.
The Kelvin numbers are colour temperatures: the higher the temperature, the bluer/purpler the light. The amount of usable (visible) light is peaked at around 4300-5000K, so anything at a lower or higher temperature would appear dimmer to the eye.
Light has to come from somewhere, so indeed, the higher luminosity you want, the more power you'd need. Assuming you have halogens though, this rule does not apply, since a discharge lamp is different from resistive heating lamp. Continuing with this assumption, the proper way to upgrade is to puchase xenon housing together with the ballast; this way it's a straight forward plug-and-play installation. You could opt for an aftermarket H7 HID kit for your halogen housing if you please, but it'd require you figuring out placement of the ballast.
I got my e-code with ballasts and bulbs off eBay myself; you could also get them from shops (eg, a local shop in Vancouver, PG Performance, sells them) for more money.

iambeetle

My A4 is 2002...

I think i might have a HID already thought...

when I light up for the first time, it is very green and bluish, and it turns to white... it looks more white than yellow to me...

if I have a HID already, how and what can i upgrade it...?

thanks a lot for your replies~~~

Black_RS4

sounds like you have HIDs...

Why do you want to upgrade your lights?

iambeetle

because it's kind of dim... especially when it's rainy....

trying to get a brighter light...

akula-ssh

There are higher power rated ballasts aftermarket. That said, I'm very surprised that you find your lights too dim. Are you sure they're aligned properly, or are they aiming way too low?

iambeetle

really...? then I might need to see if they aim nicely...

Where can I go check?

akula-ssh

Easiest is to just find a level surface with a wall in front and see where the light cut-off is: is it significantly lower than the height where the bulbs are?

Or, come out to the meet and you can compare yours with mine.

Black_RS4

yeppers, best way is to align them when pointing at a wall or garage door...