Quote:
Originally Posted by Bitchn5ive
Attachment 2855127
BM3 OTS stage 2 (Car is xdrive)
Thoughts on this and/or the log from the prior post?
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If this is the dyno sheet from your car, I would remove this tune ASAP. That is a hell of a lot of torque being made down low. That's the exact type of scenario that will cause you to blow up an engine.
From what I've read online the M5 guys don't like to go above 600wtq to avoid bending connecting rods. The N63 has weaker connecting rods, so one can assume it shouldn't go above that level either!
With regards to scored cylinder walls; based off this dyno I don't think the OTS map is "bad" but the amount of power being requested by the tune is what's "bad" (I'm going to assume it makes peak boost right at that torque spike)! If it's making that much torque at such a low rpm, you could have very likely bent a connecting rod. With the connecting rod bent the piston wont sit straight in the bore and the rod will force the piston into the cylinder wall and cause scoring.
If the tune was unsafe via timing or IAT and caused detonation, you typically see it on the piston first (either pitting or broken ring lands like already mentioned). The piston would have to get so bad, like melting the side of it off, that it would destroy the cylinder wall.