you will need Kev's O2 eliminator when using a PCIII on a 2007 XT and newer with the lamda sensor. This will help PCIII to get correct readings (lamda seems to be making things not accurate for PCIII), so you will get all benefits from power commander. This is what I am using on my 07 xtx. The iridium plug proved to be a perfect match with the Power Commander III and O2 eliminator, that's all.
Kev, please correct me if I'a wrong.

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