They got a chart on their website. 3200K is yellow/4300K pearl white/6000K a bit blue/ 8000K more blue/ 10000K purple and so on... The less K's you have, the more light output u get.

 

I went with the 6000k. Where did you mount the Ballast?

 

on the inside side of the fenders

 

i would say that 15k would be really bold and to use them as fogs to look really cool and make a statement. for your headlights use 6000k. thats what i run and i like them alot with their purpleish tint that isnt over the top. vvme.com is what i use, they're great. no problems so far

 

heres a pic of me and my friend's car. 6000k vvme on both

 

Where did you end up mounting the ballast?

 

for the fogs, its kinda tricky to explain. i just got up in there and found a safe, dry, not hot place. for the healights it was easier to find a place to mount (under the plastic thing that the headlight rests on, becareful when using zip ties and putting the headlight back in when you're done). the drilling of the headlight housing cover was the hardest part

 

yea i think there is a place to mounth the ballast underneath the headlight housing.

 

**PLEASE** don't. Those look incredibly foolish.

I strongly recommend the stock 4300k's. They are chosen for a reason, which is they provide the most light.

http://www.intellexual.net/hid.html has the best, most readable tutorial on choosing the right HID setup I've found. Please check it out (I"m not affiliated, it's just a resource I found before starting my upgrade (https://www.audiforums.com/forum/audi-a6-9/%5Bcomplete%5D-audi-a6-halogen-bi-xenon-upgrade-pics-96448/)

Slightly higher color temp is OK, and I understand the reasoning (wanting closer to the blue end of the spectrum) just don't agree with it.

Note that your projectors already diffract the light as you go off-axis, which is what causes that blue flash as a car with (good) hid's say goes over a bump. Many projectors sourced for audi, bmw, & others actually have little ridges molded into the periphery of the projector's lens to exaggerate this effect.