1 You probably have a clogged Cat unless you have it removed I couldn't really decipher.
2 You're running way to small of a pulley for the modifications done to your vehicle. Also with you being in Michigan that 160* T-Stat is hurting you more than it's helping you same goes with the Autolite 103's.
I have tons more mods than you do and i'm not even running autolite 103's. That sparkplug is way to cold for your setup. Your running rich due to your engine running too cold with the spark plugs and tstat you currently have.
Get a 180* T-Stat, Autolite 605's and put your stock pulley back on before you really hurt your motor.
Scan for KR and if you have 0* after this then drop down to Autolite 104's and a 3.4 pulley at most and scan for KR again. If you don't have 0* of knock and your still running rich ditch the zzp computer and have your stock one tuned by a knowledgeable individual who is familiar with our cars. That is the only way to get your car running the best it possibly can with the mods you currently have.
Also give this thread a read. It might help ya a bit.
http://www.grandprixforums.net/safel...car-17482.html
