NGK IRIDIUM IX SPARK PLUGS
 

Should I use heat range 7 or 6?? 6 is standard and 7 is for mild tuned but I was thinking how hot these things get then 7 maybe a better option even though my car is not tuned??

Any thoughts guys?

I use the 7's. my mods are td05 turbo, 550 injectors, de-catted and walbro fuel pump.
not sure if that helps

I'm going to go for them:thumb:

IMHO stick with NGK PFR7B and forget the iridium.

Why??

Because the PFR series are double platinum - both the electrode and the ground are platinum tipped, and so are more durable than the IX ones, where only the electrode is iridium

Although they worked fine, on replacing the iridiums in my engine, I found the ground electrode had a noticable crater which had the effect of increasing the effective gap.

JohnD

Because PFR7B are cost effective, work well, last a long time and are reliable.
Do not be taken in by the glossy advertising for iridium.
I and others have had iridium insulators break. Cost me a cylinder head and turbine wheel.