Iridium or Ruthenium plug to replace a copper plug in performance LS

I'd pay close attention to the ground and center tip materials for each specific model. There are "Laser Platinum" plugs that have a nickel ground tip and a claimed lifespan of only 40k miles compared to 90k miles for proper double platinum tips. Very confusing when they are specified for the same application and the "superior" double platinum plug costs less...

Eg:
Laser Platinum w/ nickel ground, 40k mile life: https://www.ngk.com/product.aspx?zpid=30699

Laser Platinum w/ platinum center and ground, 90k mile life: https://www.ngk.com/ngk-5987-plzfr6a-11s-laser-platinum-spark-plug
Yep, the Denso plugs on almost all the Toyota 2GR-FSE/FXS/FKS, as well as the smaller variant in the Lexus IS250(4GR-FSE IIRC) and 1UR-FSE/2UR-GSE/2UR-FSE only have Pt on the center ground strap and not the side straps. 60K life. It’s done so if the main strap is carbon fouled, a spark can still happen.
 
I'd rate Iridium and Ru plugs about same. Ran Ru plugs in Forte for over a year and went back to Iridium only 'cos a coil failed and I was pulling things out for inspection and decided to change plugs too. One new coil so far, but gonna replace the other 3 as well; wife's car thus need it to be more dependable. Kept Ru plugs aside JIC.
I believe that this is the trap of the Ruthenium plugs. They put more stress on the coils and take them out sooner. So buyer beware.

I put a set on a Toyota Matrix. Seems like everything should be a go. But they were installed last fall, and wound up ending the two 17-year old OEM original ignition coils; the were misfiring and number three finally tossed a CEL light saying it was misfiring badly. The environment was stressful, as a failing fuel pump would cause a lean-running engine, but at least with stock or Iridium TTs, it was the plug and not the coil that took the suffering.
 
I don't think Ru plugs were the reason, car/coils had over 100k miles on them before one coil failed.
The ones that died on me by misfire had 220k+ but they weren't dying when they had stock iridium plugs. The stock plugs were wearing out faster but the coils weren't misfiring.
Whatever design this plug has, it's not the same as what Toyota OEM or the Denso 4701 has.
 
I don't think Ru plugs were the reason, car/coils had over 100k miles on them before one coil failed.
Agreed. More likely failure was due to the physical manipulation from the removal and reinstallation of what were old, high-mileage coil packs. Some things just can't be avoided; you have to do one to get to the other. That's why it is recommended to replace wires, on cars that have ignition wires, at the same time too.
 
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