I've read many complaints about the 8.1's fondness for destroying plugs, and apparently mine is no exception. But does anyone understand why? What are the mechanics/chemistry behind this problem? I have a low mileage 8.1 and keep factory plugs in it. Two weeks of hard driving, maybe three and it feels sluggish again. No codes. Pull the plugs, they don't look too bad, but I do notice the electrode is a little beat. Replace plugs and look out, more power then I could ever need. Having Chevy big blocks and even modified motors with high compression with powerful ignitions, I find this strange on a stock motor. Thoughts?

 

Is this platnuim plugs?

 

Iridium