Video of pull. Notice the smoke in the right rear view mirror
https://www.dropbox.com/s/mqx7wqfzsj7b16y/endgame.mp4?dl=0
https://www.dropbox.com/s/mqx7wqfzsj7b16y/endgame.mp4?dl=0
Endgame setup- BW s257sxe
- Thread starter iamareios
- Start date
do you have logs you can post from the previous revision which showed knock to this revision for when the motor popped and any logs before the motor popped on this revision?
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It seems on the rev3wot log you had a string of knock starting at 5k and ending around 6k. Was that log the log right before the next revision where the engine failed? the cylinder loss log made almost no power at all so it seems like the compression was already gone and the engine had failed when you were taking that.. Rev3wot log also seems very unstable as the other logs are more linear in terms of power output. 3 of those logs show knocking between 5 and 7k. It could have been your timing that was the issue. Either way something was going on in the 5-7k range. I used Virtual Dyno to compare the logs and to see different points. Not sure if that is the most reliable way.
Yes, there is KR present in rev3 wot log, but highest logged was only 0.59 KR with it descending. This was the log on the revision just before the engine blew on rev4.
Just because there was .59 knock max doesn't mean that knock didnt damage a component.
You saw that knock under heavy load and high stress conditions. The damage could have happened at that point but the engine didnt completely fail until a little while later.
You were on e30 right? Are you sure the condition of it was good? Maybe it was too much timing on a bad batch.
I find that hard to believe. That's my opinion though.
.59 KR does not take out a piston. Let alone 2 at the same time. If it was bad gas, there would have been more KR. I appreciate your input though.
sent from tapioca
I get that it isnt "big knock" and I'm not saying it was a crap tune. It sucks you're dealing with this.
I understand why he isn't going to warranty the motor. Yeah it was "built" etc and should hold up under the extreme conditions however you were able to go 7k miles on the motor he built, under a bunch of driving conditions with I'm sure more than those pulls alone. If he had improperly assembled the engine then you would think it would fail sooner.
Now if you were on all stock components and stock ECU tune it would be hard for him to argue. Have you torn down the engine yet? I would measure everything, photograph all components and measurements. Build a case on your behalf then see what he says
Thank you for your understanding. I have not disassembled the motor yet. I have yet to pull it out. I'm currently waiting on results from injectors I sent out for testing.
sent from tapioca
shaneski
Greenie N00B Member
Do you have logs of the 91 tunes that were hitting KR. If it's up near 3.0 at high rpm on pump fuel it's cooking pistons no matter what they are made of.
Yes. It wasn't until the 4th rev on the 91 tune we experienced the KR.
shaneski
Greenie N00B Member
There was some detonation going on in the 1st 2 logs that may have caused some weak spots on the pistons, since it was just 91 with the amount of boost wouldn't help due to there being no meth or eth to cool the combustion heat down and spinning it to 8000rpm.
Injector test results came back with all 8 good. Ruling out anything with the fuel system at this point. View attachment ANDREW BUCUR 12-30-20 FS.pdf
sent from tapioca
sent from tapioca
Enki
Motorhead
What cams in this build? There could be an issue with the IDCs if you're not running stock cams.
Otherwise, the only alternative explanation I can think of is as follows:
High RPMs causing excessive ring heat into ringland fracture; could be averted with a looser ring gap.
Logs look fine and e30 should be more than enough for detonation free operation.
Otherwise, the only alternative explanation I can think of is as follows:
High RPMs causing excessive ring heat into ringland fracture; could be averted with a looser ring gap.
Logs look fine and e30 should be more than enough for detonation free operation.
Looks like the next step is to start tearing down and measure the ring gap. Hopefully they aren't that torn up but you should be able to measure the other two cylinders since they should all be the same
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