AC Delco .R44TS plug knock???

[sick GN]

I just changed the plugs in my car and I realized that what were in were AC Delco .R44TS plugs. When the car was idling it was fine but it did seem that it was gettin too much knock at WOT. Could the main reason be because of these plugs?? Are they even good for GN's period?? Thanks Just wondering, now I have CR43's.

 

[Mr URL]

The 44's are for bone stock cars. Use 43's or 42's in modified vehicles. It's just a cooler heat range. CR just has a thicker electrode.