Putting HID kits in housings made for halogens is illegal and ticket worthy in any state. Halogens and HID light patterns are very different and that is why HID's should only be used in projector housings. Halogen housings with HID's will create a blinding glare which can be somewhat controlled with casper shields or by aiming them way down which makes the point of them uselss.
As the other person said, the k rating refers only to the color. For optimal light output you need 4000k-5000k. Less than that is yellow which is for foglights and anything greater than that is harder to see....and in my opinion looks stupid. If people behind me have an HID kit in their car with improper housings i get behind them and turn my brights on because they are stupid and can feel the pain of getting blinded in every mirror.
Also, HID kits come in 35w and 55w with 35 watts being the most common choice. Finally, if you do decide to HID's which I don't recommend you need to get the addition relay harness to prevent the power on startup from destroying the light switch.
I've got 4500k HID's in my Honda but I have projector headlights by TYC which have been DOT approved and comes with a card in case I get pulled over.
If you are really looking for better light output you either need to retrofit your current headlights (Which is still illegal) but will not have any glare. Or, get Sylvania Silverstars. However, in my experience the light output is great but they dont last long at all.