Oh man that is nasty.
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Six_Shooter's money pit and time vampire... v.240Z
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I have to pull the data log from my AEM Failsafe gauge to see if there was any sort of spike, but I don't recall there being any at the time.
I think I've just abused the stock parts for long enough that they decided to give up.
I believe that #4 let go first, not sure whether it was the skirt or the ring land first, but then there wasn't enough space for piston and rod and extra length under the head so the rod then broke, and that breakage caused lots of debris and took out the #3 rod...
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Usually hit 6300 to 6400 RPM. A little lower in first, I think I had the shift light set to 6000 RPM for first gear. I have taken it close to 7000 RPM a few times.
I only think the rods failed because the piston failed first from what it looks like to me. #3 was definitely collateral damage.
I've already talked to my engine builder friend, about the road to rebuild, and I'm going to build this for my end goals, with aftermarket rods and custom pistons.
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Nice Carnage!
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I ventured back to the beginning of the thread, right around the time where it cooked a head gasket. Looks like the same cylinder? May have slightly uneven airflow distribution with that upper intake. Have any old spark plugs, or the current ones to peek at? Im curious to see where the AFR's were at just before it went kablooey.'86 Grand National
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Not enough ring gap, looks like. Detonation severe enough to break off that much of the ring land would show up in you cylinder head combustion chambers, or on the undamaged area of the piston as little pockmarks. What did you open the rings up to?
Keep in mind hypereutectic pistons require a much larger (20 to 30 percent, in many cases) top ring gap compared to a non-hypereutectic piston. The top rings on my 3.4L are gapped at 0.028", compared to 0.018" that would normally be fitted to that engine. All because I'm running 3400 hypereutectic pistons.
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