Originally Posted By: PandaBear
E3 may have some advantage with weak coil when the piston speed is low (i.e. lawn mower or single piston engine) so the flame propagation is slow. There are lots of sharp edges on E3 with all the side electrodes, cuts, etc. So it does last long for the same material as other normal plugs. However I can bet you any fine wire precious metal plug would work just as well for just as long in every single application.
I concur. I will be sticking with iridium plugs in all applications, until they fail me.
I think that when iridium plugs first came out, people were afraid of them for any number of reasons. But some people could have actually provided true testimony that the plugs performed poorly, misfiring and such.
For example, on my '97 Volvo 850, RockAuto.com lists a "0.028" plug gap for the NGK IX Iridiums, yet a "0.044" plug gap for the Denso Power Iridiums. They both, also, say that you can NOT gap these plugs... which is NOT true. You must simply be very, very careful with these thin tip electrodes. It's no wonder that those who tried the NGK IX's called them "smooth" and "flawless", while Densos typically were not regarded as good as the ol' faithful "copper" (which is clearly coated with steel or nickel). When gapped properly, I believe the NGKs and Densos would perform almost identically.
From the looks of it, tho... I'll be sticking with the NGKs in my application, merely because they seem to work right out of the box. And I like that a lot.