How do these pulled NGK spark plugs look?

[punisher]

Plugs on street driven vehicles are run on cold engines, on hot engines, at idle, part throttle, WOT, under load, during coast, with who knows what brand, or type of gas whose composition changes constantly.

Contrast this to a race situation where the plugs are run under one prevailing condition, with a known fuel. At the track when you finish a run you shut the engine down after the run so you don't mess up the plugs. Plugs come out and go to a tech guy {from NGK, Autolite, Champion, etc) with 20 years of experience with a loupe/magnifier who makes the call.

At best you can see gross problems on a street plug. Excessive oil burning, gross rich/lean conditions and maybe pre-ignition. Making any sort of nuanced diag from a plug on a street vehicle is pointless. Just the myriad of gas additives in pump gas leave deposits that throw a diag out the window.

 

[Trav]

Originally Posted By: Geauxtiger
For my personal learning, I would love to hear the science behind those firm conclusions with the limited data at hand. Not meaning to be a rear end. Just want to understand.


They look like any other decent running turbo engine plug with that many miles, they were running fine.
Boosted engines run colder heat range plugs for a reason. These plugs are not showing any sign of detonation or pre ignition the color looks good and the minor amount of deposits are nothing unusual in a boosted engine.

 

[Geauxtiger]

Originally Posted By: Trav
Originally Posted By: Geauxtiger
For my personal learning, I would love to hear the science behind those firm conclusions with the limited data at hand. Not meaning to be a rear end. Just want to understand.


They look like any other decent running turbo engine plug with that many miles, they were running fine.
Boosted engines run colder heat range plugs for a reason. These plugs are not showing any sign of detonation or pre ignition the color looks good and the minor amount of deposits are nothing unusual in a boosted engine.


Thanks Trav!