not sure on the iridum's. Gap we run is .035"
You are likely rich since aftermarket slip'ons usually like leaner main jets. Likely the carbs may have a stage 1 jet kit and is dumping too much fuel too.
Oh, and by the way. I have a GOAT! You guys just have a couple of badged imports (sorry to bag on you but the new GTO's never have really earned the title in my opinion - they are one of the few offerings that are worth having though).
Sean
The original GTO was nothing more than a plain looking car they stuffed a powerful motor in. The new version is a plain looking car with a powerful motor. Although I do think Pontiac screwed up calling it a GTO. Notice the new Holden to make it here is being called a G8. I really hope they actually bring the Ute(El Camino) here. That would be sweetness.