Hello! I purchased some NGK Iridium IX Spark Plugs BKR5EIX-11 # 5464 from amazon (linked). I removed one of my old plugs AFTER receiving these ones in the mail. And it has Mercedes logo and says NGK R.
Upon searching the forum I see a lot of people talking about heat range, etc.... And I saw one person asked if he could use NGK #4969. And someone replied "bkr6eix11's ".

I am trying to perform a tune-up to increase performance and maintain a happily functioning car. No point putting incorrect spark plugs in... I'd rather the old ones leave them in.

And then I looked in the owners manual and it says "NGK PFR 5-11" (or Bosch, but nah), and that has me confused even more!

I have a 2004 Chrysler Crossfire Limited with 144,xxx miles, and has original spark plugs. (I purchased from a coworker's son and he bought the car at 60k miles, never changed the plugs).

 

Those plugs are fine. On an NA, there is not much you can do with mods that would require a heat range change, on the SRT6 it's another story.

 

Thanks! Amazon said they fit. But numbers weren't matching so I wanted to check!
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