High O2's Numbers

[p&d]

I had my fuel pressure set to 45 psi line off. Trans + and extender chip. At wot my o2's are 890 too rich. I lowered my fuel pressure to 35 psi line off and its down to 845. Any idea why this is happening I have boost at 17#. I get 2.1 to 4.5 knock. The car feels like its running out of power at WOT it sputters and surges real bad.