Originally Posted by SkunkWizard
I know NGK is the "Go Too" but the P/N for Denso Iridium's from the Denso site is #IU31
(Denso's have been a personal preference of mine because of my experience with road racing)
denso does make a better irdium plug because the hold the patent for the original .4mm tip size. ngk and others need to use a larger tip and smaller is better.