This Site has some good information on iridium plugs that may help you guys choose between the Denso And NGK Iridiums.

http://www.spark-plugs.co.uk/pages/t...park_plugs.htm

 

I would go denso....i changed mine recently and they are just amazing....I believe ur stock sparks/coilpacks are all denso as well.....I learned the hardway when 2 of my coilpacks got stock into the boots....

I would stick with what comes factory...

 

I have seen dyno runs for the Denso Iridiums a multitude of times. Bottom line is they make more power even vs. brand new NGK plugs. Bottom line is they don't "make" more power, they just retrieve what power that your car has been missing.

 

dyno runs can be so manipulated.

While it may not be directly comparable, I tried Denso Iridiums at the track against NGK Platinums and saw no improvement in either MPH or ET.

 

Very true. There are also alot of environmental conditions that can be added to the list of variables.

The specific one that I am thinking of was a "back-to-back" run with a NGK vs. Denso plug change. Total time elapsed, 45 min, with three runs each to verify reliability. These were without correction factors.

I'm not trying to preach it, but I personally believe in them, just sharing my experience.

 

2001 LEXUS GS430 4.3 L - V8 IK20 gap 0.044
http://www.densoiridium.com/
Are these the same as oem ND iridium.