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NGK 300ZX Iridium Spark Plugs Code: 300-2667_8_9 Name: NGK 300ZX Iridium Spark Plugs Price: $60.00 Description: Stock Boost Levels up to 15 psi: Stock Plug PFR6B-11B, Smooth Daily Driver “7” Heat Range: Stock Turbos (15+ PSI level), Sport 500s. 530s, & 600s. Great for street use.
“8” Heat Range: For those who race at high boost levels and any upgraded turbochargers. Good for nitrous as well. Great for street use.
“9” Heat Range: Race use only! Great for high boost and nitrous use. Not recommended for daily driving.
Set of 6 included
Concept Z’s 300ZX Knowledge > mine > yours…so i think i’ll listen to what they have to say about which plugs to use. If they do end up having a short lifespan, then i’ll prob stick with coppers…but until that happens, i’m taking the advice of the pro’s on Z’s.
I ran coppers all last summer on stock boost, and it didn’t run as bad as you think (but yes, it could have run better)…this year i will not be running stock boost…and so, i’m going to be running iridium’s…getting one step colder than stock as well…just incase i plan on running more than 15psi…which i eventually do.