Misfire in 4th gear when reach peak boost, BMW N55 6MT M2 upgraded turbo.

Misfire CEL consistently 4th gear after reaching peak boost.

Car is 6MT, Direct inject only set up. E50 fuel. 26psi peak. 34000 miles new.

1-3rd gear runs perfect all rev range. redlining without a problem. Strongest BMW coils conversion(2x energy over original equipped ones)

Spark plug NGK 9 heat range, gapped 0.024'', upgraded high flow injectors(can support 800whp). Compression test/boost leak test with perfect results.

Rail pressure is healthy, boost control is healthy, no knock event.

Any idea what could be wrong with the log? Appreciate it.

https://www.bootmod3.net/log?id=65d17e64aa2e4257ac11b12e 4th gear only, misfire CEL at 5600rpm

https://www.bootmod3.net/log?id=65d04b1ca1f7375a14147d40 3rd and 4th, misfire CEL at 6100rpm

At a glance it looks like you may be running out of injection window, and already running pretty aggressive lambda. At a certain point if you can't deliver more fuel, reducing air is your option.

It jumps from 12 to 18 AFR right when the graph stops. I'd say fuel is the most likely issue. You mentioned injectors and other related mods, do you have an upgraded fuel pump?

Lack of fuel will usually show a tapering up, a sudden increase is usually down to an ignition misfire - as 18 is usually the maximum value, it may be the ignition cut?

Got it all figured out. It's the ignition dwell pre-load tables from the tuning platform(loaded the dwell tables for higher energy coils). Fixed the issue by changing back to "OEM" tables without touching anything else. Of course, I've done a lot of re-gapping, swapping, adjusting injection SOI/EOI, etc. to test. Thanks for the input guys.

Tested 13 pulls back to back. Cheers!

https://www.bootmod3.net/log?id=65daf28cc0c9c9791cfa8d96

Excellent!