Is it ok to run Bosch Plat 4 plugs?
Check the left side of the cylinder head there is a warning label specifically requesting Iridium plugs only...at least there is on my motor...you can run the Bosch but there maybe a Performance issue/durability issue.
And I should state to err on the side of caution, that if one puts nitrous or a Turbo on your car, it would be best to ignore this warning and go with colder plugs by several heat ranges to be less likely to provoke detonation.
So we (GT owners) do not need Iriudium Plugs...I am kinda confused so try and bare with me...
If I run regular octane (cheapo stuff) then a Platinum Plug is fine (since it is "colder" meaning it can endure lower temperatures)
I run an Iridium plug ("hotter" meaning it can enure high temperatures) it is over kill for stock unless I have NO2 / a Turbo / or both, where engine temps are hotter and the higher temp would be a "normal" operation for these mods.
Is this what you are saying...or am I reversing something... (Platinum < Iriudium) for temp rating...I hope this makes sense...anyway I am out of the office in a bit but I'll be back around later tonight.
Oh one more thought, since the GT is a high reving engine for its power band then wouldnt' the Iridiums be better for longer life and less chance of detonation.
Sorry bout the length...I am doing some Calculus III while thinking here