Best Sparkplug ? ?

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Senior Member
whats the best spark plug to run, im currently running denso iridium 5204's in my b18a
There are poeple on this board that claim the Iridium is the plug to use. Personally I don't that the they show a large enough power gain with an NA engine to be worth $11 a plug. Especially when $11 almost buys 2 sets of Copper NGK plugs.
well, i personally felt a power difference between an ngk and the iridiums. i didnt need to pay the 12 dollars a plug do to wrking at auto zone. haha. ive seen better dyno readings out of the iridium plug as well
Do you have any dyno sheets that compare the NGK Copper plugs and iridium plugs in the same NA engine?
As would I. If the sheets showed a significant gain I would pay $45 a set to run iridium plugs.
should i just use 2-3 degree colder plugs or just run iridiums when i run nitrous? i want to run nitrous but im not exactly overjoyed knowing my engine can blow up because of a stupid melted plug... i've ran 2-3 degree colder plugs before and they work fine but i want to be "safe."
If you are worried about running the Nitrous, trim the ground strap back on the plug of your choice. This is where the heat gathers that causes detonation, which in turn melts the plug. Look for the shortest, fattest ground strap you can find. If I'm not mistaken, someone is marketing plugs made for Nitrous now, though I can't remember who.