As far as the 2 step colder plugs... that probably wouldn't be a bad idea to start with... heck I was using colder plugs in an n/a engine to prevent detonation/pre-ignition.. not sure what mine was.. I think I got pre-ignition from what i'd read at the time.

And you figure I was making what, at least 150 hp less than you...

04 Subaru WRX "Eurosport bling bling fast and furious tokyo drift" "They have diarrhea of the mouth, and constipation of thought"