If you haven't read it already, read this http://www.grandprixforums.net/safel...0-a-67580.html... twice
then bookmark it so you can get back to it.
Truthfully, every factory car will knock a little. Usually blips of 2-3 on average, not enough to cause problems because most people don't beat the piss out of the car 24/7. As long as you run 91+ it will be fine. To get the KR gone, you really need the flow mods and a tune, even on a stock pulley you can tune it out and make the car run better.