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k20/k24 on M150 blown on dyno.

MoTeC M1 Software Tutorial

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I attached the the data log fie event is in the last 4th gear pull after lifting foot.

Attached Files

You need to post the .ld file -- the .ldx file is just the extended data of settings or changes.

I added that file

Sorry for your loss!

Based on the head & pistons, it sure looks like #2 (or #3) was running much leaner than the other cylinders. Could you have had a clogged injector, and you were overcompensating to get the lambda readings in range, thus the reason the other cylinders have so much deposits like they were running way too rich.

Did you notice any misfiring at low RPM (i.e. rough idle)?

Did it fail on that second start (around 47 sec) where it immediately rev'ed to 3800 RPM?

There is no oil pressure data, that might give you a clue if you had a bearing problem developing.

No ideal was smoth. No misfire. And car is shut automatically after pull and I try to restart by lifting my foot from clutch but it dies again.

https://youtu.be/uDB9vv1T09M

That's the ideal video

Based on the pictures you've posted I'd say the failure is purely mechanical. It looks to me like one of the rod bolts has potentially been over tightened (based on the necking visible around the rupture point) and the other rod bolt has then snapped off at the root of the first thread. There is no sign on the skirt of the piston that it has seized in the bore and while we don't have a picture of the bearings or crank, a bearing failure significant enough to cause this would inevitably have the rod cap blue or black from heat.

That's the main Bering picture.

Attached Files

The pictures you've added show no sign of a bearing issue. There is some light scoring that is indicative of some debris passing through the oil but certainly nothing indicating a bearing failure. I stand by my original assessment.