Spark plug replacement - denso iridium performance

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Fuji4

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Replaced the plugs at 98k miles. I swear it’s smoother and stronger accelerating. By like 10%. Am I crazy? Didn’t think it would do anything.
 

djkaosone

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Oh, I swear by denso iridiums long life too! Better than NGK iridium lasers or any other plugs... you'll definitely feel the difference with the turbo. Speaking of, I need to replace mine too, it's been a few years. I typically replace mine every 2 years.

Oh btw... thanks to you, I'm 100% Amsoil, for all my cars.
 

ktm525

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Likely project completion placebo but hey if it feels good then all is well. Lets see 375 HP engine and a plug replacement gets you 37.5HP? Best $80 spent ever..lol.
 

djkaosone

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Likely project completion placebo but hey if it feels good then all is well. Lets see 375 HP engine and a plug replacement gets you 37.5HP? Best $80 spent ever..lol.

@Fuji4 has a pretty awesome tune and plugs make a world of a difference, especially on forced induction cars.

@Fuji4 how bad were the electrodes on the old set? If they're pretty worn out, I'd recommend running a 1 step colder plug.
 

Fuji4

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Ohh thats right. Lets see the old plugs!
I should have taken a picture. They were not too bad. No weirdness to speak of although I didn’t check them for electrode degradation. Nothing jumped out anyway. Nothing fouled.
 

gsxr

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I changed mine at 125kmi, old ones looked fine, and I could not tell any difference at all with new ones.

Be careful when buying NGK plugs, there are a ton of counterfeits on the market. Buy from a large reputable vendor (i.e. FCP Euro, RM European, or the dealer)... not eBay or Amazon.
 

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