I originally use to use a Odonnell 97T which gave my go a nice smooth idle but later I found the P3 gave them a better response. I've bounced around trying O.S,Trinity Ex-Tech's and now the GO T3 plugs. The Trinity's held up better then the P3's in my opinion and the T3's I've only tested at 2 races and seem to hold up real good with the right tune. That's with 30% Byron's race driver 3000 Gen 2.