Unstable Bob -
I keep thinking I have seen all the spark plugs out there, but there's always
a new one I have never heard of. A "no indexing" firing tip in a Lambo, of all things? Maybe this is the secret to theclencher's success.
I have Denso Iridiums that seem to be working fine right now, but Saturns also use a "waste spark" system that reverses the polarity of the firing of the plug :
Spark Plug Comparison Test
I think your Ecotec does as well :
INVESTIGATING GM'S COMPRESSION SENSE IGNITION
... The ECOTEC engine uses a speed density-based fuel injection system, along with a waste-spark electronic ignition system. The waste-spark ignition is part of a unique Compression Sense Ignition (CSI) system that allows the powertrain control module (PCM) to determine proper engine phasing (cam position) without the use of a separate camshaft position sensor mounted near a rotating engine member. This article will explain how the CSI system operates. We'll also document new misfire diagnostic techniques that are made possible by die system s unique design. ...
I will be interested in your long term performance because I read at saturnfans that certain spark plug designs are susceptible to being fouled more quickly than others. My Denso's should be vulnerable, but they're working like a charm (knock on wood).