Have been getting knock every so often did spring cleaning fule filter less than a year old, drive car mostly on weekends. Use to run race gas tiered of changing o2 sensors so am running boost around 15-16 set fule pressure to 45 psi at wot sits at 60psi. now running 91 pump gas turbo (tweek chip older) for 60 lb injectors. As of recently knocking more often, changed plugs from autolite iredium witch worked ok when took out they looked a little whiteish,tan on porclin no speckels. electrode area little blackish not bad. So I went back to ac cr43ts they allways worked good. put a dutwiler neck stock ic in 2 weeks ago boost went up to 20 pci had it set at 15-16 on old ic so I figured was flowing better but still turned boost back down to 15-16 I get different readings on scanmaster o2 some times 750-780 up to 830 and knock once or twice has went 2.3 another time 4.2 at that one o2 was 839 and i was in drive and rolled into throttle slowly to watch out for knock and to watch fule press, at 15 lbs boost was going ok and then about 1/2-3/4 throttle knock guage started climbing got out of it as was starting to go to red looked at scan master 839 and 4.2 cannot figure this one out if anybody out there with any Ideas please help. oh tps .42 and 4.40 wot 
