I honestly think that it depends on the brand of bulbs you got....
I've recently swapped my aftermarket HID's 6000k for a factory set HID's.
The aftermarket 6000k is pure white, like what they are meant to be, but with he factory HID's, I put in a pair of cheap ebay 6000k bulbs, they look as green as your 8000k.
So if you are after "white blue", I'd suggest going Phillips, they are only $60 or so.