[MichaelNRW]

Originally Posted by aci4

So is there a difference between the NGK 96206 vs 94201? You mention the 96206 is for the B58TU1 (2020 m340i) but I noticed the folks earlier in the thread running the 94201 version on their B58TU1 engines. I’m also not tuned.

B58 Gen 1 = 94201
B58 Gen 2 / S58 = 96206

[B58Bandit]

I went NGK gapped to 0.025 per mission performance recommendation w their tune. Changed the stock plugs probably a week after the tune at around 25k miles. Now have 31k miles and No issues thus far.

[hayko_M340]

60K Mile Update: It was definitely time for plugs again as the idle started to get choppy and it would hiccup here and there even though no misfires or CEL. There was a notable drop in MPG as well. Car felt very sluggish and powerless at times especially when under high load (Hot outside, AC on, etc.) Went with NGK 96206 this time once again gapped to 0.025 opposed to 94201 like last time. Difference is there for sure, much smoother linear power delivery and no hiccups. It has been on stage 0 stock map on 91 fuel about 90% of the time since the last plug change and they were still this cooked.

[NightOwl-M340i]

How often should plugs be changed for stock vs tuned?

[AM340iMiami]

You’re going to get a wide range here. For stock, you should be fine changing them anywhere from 60-80k miles. You could probably go longer.

Tuned, 30k maybe.

[RCKYMTN M34OI]

Since I saw there were some questions .. this video does a good job explaining the different part #s and differences in gen1 vs gen2 plugs