That is a combustion mark on the side of the piston. What was your WOT AFR? Verify ring gap if possible.

 

This aligns with cylinder binding to me. Large chunks of ring lands broken and damaged or torn off piston crown.

I'm leaning towards mechanical just because:
1. We see zero peppering/sandblasted look on top of 2 bad pistons from suggested "constant or heavy detonation".
2. We're told plugs look fine. Simply soaked in oil instead of "extreme detonation" where they'd be exposed to extreme pressure/temperature that'd start melting them or at least we'd see "popcorn" like, so melted aluminum material from the piston be present.
3. If he had misfires he would most likely feel it with 1 cylinder never mind 2. Hondata, being basically OEM ecu also would've thrown a CEL for sure.

EDIT:
This unfortunate event makes me want to help but also to learn. As I research further, another thing to check:
"What we're going to be doing here is inspecting the edges of our ring end gaps, and what we're looking for is a polished appearance to our ring end gap. If we're getting that polished appearance, that's the very first indicator that our rings are starting to butt together, and that's a clear warning that we've gone too far, and in fact we'd then need to increase our ring end gap by a couple of thousandths of an inch. If we've got no sign of that butting though, if there's no polished appearance there, and we are understanding the risks involved and prepared to take them then we can then rebuild the engine with a new ring set and reduce that ring end gap slightly. "

 

Very unfortunate for both parties. Those bearings and the burn on the top of the piston look great.
What fuel octane are you running?. What happened to the engine before the rebuild?

 

Hi all, I've contracted Evans (Jeff) and he is reviewing the tunes/logs from my tune. Inline Pro is to be measuring the bores at the beginning of this week to make sure we can even still stick to a 2.2 for the rebuild, and discuss options from there. I'll keep this updated as things unfold.

 

Good to hear. Would love to know what Jeff says about the tune. Keep us posted.

 

Update from today, block is trashed. The scoring is too bad to clean up even at 87.5 bore.

I'm really not interested in sleeving the block, I want OEM reliability. Ugh. Happy Friday!

 

Other than describing the damage they caused, what's Inline Pro's solution?

-- Chuck

 

 

Does anyone know if Inline Pro has the same engine builder(s) as they always have?

 

Update:

I wanted to give all parties a chance to respond before posting an in-depth update.

Evans reviewed the logs and showed that the AFR was 13+ and encountered over 100 counts of knock in a single gear pull during the time of failure. The motor leaned out like crazy, he said he was surprised that this lasted as long as it did. That's what killed the engine.

Why did it go so lean? When the engine was being built, I was told that I would not need a re-tune. (IP assumed the engine was tuned when it was healthy) I followed that guidance. I have since learned that if I had a tune done on a motor that was having blow-by issues, then had that motor rebuilt.. now the new motor is sealing in all that air into the cylinder instead of it blowing by - causing the extreme lean condition.

I'm disappointed in myself for not thinking of such a basic thing. I've been wrenching and modifying my own vehicles for 15 years now and didn't think to myself that this thing should get a re-tune because of the blow-by. Very expensive lesson learned.

So where do we stand? Well, inline pro are doing their best to source a good donor block and are going to waive most/all labor to rebuild this. At minimum I'm looking at new pistons, rings, engine bearings, headgasket and machining the donor block. We're shooting for 2-3 weeks from now to be running again. Inline have been great to work with throughout this and John in particular has been very patient with my million questions about all of this. For anyone in the future that reads this, I would not hesitate to get work done by Inline again.

Anybody have a good donor f20/22 block they want to get rid of? Ha.

Thanks all!