I'd just stick to the stock CR8E if I were you. You wont see much difference out of changing to iridium. As for holding up longer I think the Iridium's actually foul out easier but dont quote me on that.
My main idea was I live at 1200' elevation and I ride in Flagstaff, Az Sunset Crater Volcano National Monument Cinders elevation from 7000 to 8000' elevation so was wondering if it would hold up better to constantly changing elevations and atmospheres?
Here is some info I found for Denso Iridium plugs and it sounded really good, but still am wondering if anybody has had any luck with them yet?
Q. What makes Iridium better?
Until recently, platinum was considered the best material to use on the top of an electrode because of its durability. However, Iridium is 6 times harder, 8 times stronger, and has a melting point 1200 degrees higher than platinum. Put that into a harsh environment such as an engine piston chamber, and you have a spark plug that can resist wear much better than platinum. Additionally, the DENSO Iridium Power alloy is so durable; it allowed our engineers to produce the world’s smallest center electrode (.4mm)
which reduces the voltage requirements
, concentrating its sparking power. Also, its smaller size, combined with the tapered U-Groove ground electrode
, allows more room for the flame kernel to develop and produce a more efficient combustion.
Q. How long will Iridium Last?
Iridium use represents the most significant technological advance in automotive spark plug manufacturing, since platinum was introduced in the early eighties. As vehicle manufacturers produce increasingly complex and efficient automobiles, there is a greater need for long-life plugs that can tolerate leaner fuel mixtures and improved combustion processes. DENSO has responded to this need by developing its Iridium alloy
, originally for OE applications. For example, many newer Lexus’ and Toyota models carry an ultra long-life Iridium plug variation (.7mm with platinum tipped ground) that is capable of up to 120,000 miles of service. DENSO Iridium Power plugs, with their .4mm center electrode
, have been developed for performance applications. Because gradual wear will “round-off” firing points over time, the concentrated firing power and voltage requirement
benefits will be reduced. For this reason, DENSO advises replacement after 30,000 miles.