If you'd search, you'd find this, but here we go

. The 6097/3330's are not Iridium plugs. The IK22/IK24/NGK6988's are iridum plugs. They're made of different metals and thus serve different purposes.
The iridium plugs last longer, but are more expensive. Rumor has it that the copper plugs tend to make a little more top end power, but I haven't seen anyone post a dyno showing that.
So, all that said, anyone tried the NGK 6988's like I asked? I'm just curious how accurate sparkplug.com's cross reference is.
LLCoolJ -
Good idea, I'll do that

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