Joe: does that still hold true today, as in the last couple years or so? The reason I ask is that our engine builder as well as some of the S/SS guys I've talked to seemed to feel like the *quality* of the AC plugs has gone away the past few years, which is why they are all going to NGK or Autolites. In fact, I believe it was Moparts that told me he was at a parts vendor's tech conference somewhere and the AC rep told the crowd that the AC plugs were being made by Champion?
On the first L72 we had on the dyno, we made right at 30 pulls with it, and it had a stumble and rough idle with a couple different sets of AC plugs...the NGK's smoothed it out and picked up the power.