Paul, In my attempted explanation of what caused a piston skirt to collapse, I didn't know anything about something getting into the #5 cylinder. That could have been in the nearly 1400 posts somewhere, but I missed it. I also thought the bearing failure somewhere along the line was more serious and since I know you like a tight quench, I could see the piston contacting the head in a failure situation and collapsing a skirt. Your explanation makes just as much sense and you were there! When I began building engines decades ago, pistons came in a box with the nominal size on the box only, not actual measured sizes. It was up to the builder 100% to measure each piston in several places, do all kinds of math and averages and either hone each cylinder to the piston or hone to an average. Cast pistons were usually +- .0015 through a set and forged .003. As you know even today, forged custom pistons are still kind of all over the map. It's very unfortunate you guys and the engine owner got bit by this series of events. There are always a few rock throwers, experts chiming in from the sidelines as other's struggle. It's just more public with the internet and message boards. I doubt very seriously you would be in business for decades and have a reputation where people are willing to send their engines from all over the country to have your shop work on them. So to implicate that without a public forum you would have washed your hands of this engine is unfair IMO. Again, WE ALL MAKE MISTAKES. The shop I have worked out of for 30 years 5 years ago had 8 of the 10 top qualifiers in NHRA Stock and Super Stock at the US Nationals and is a builder of Australian Pro Stock engines they ship back and forth all year. 2 man shop. Mistakes are still made, few and far between. When they happen, just like this Pontiac, the problem is eventually found and corrected.
One of the worst I had happen that relates to this Pontiac, happened on the dyno. We had the jam nut that holds the air temperature sensor in the Superflow air hat vibrate loose and fall through the carburetor of a new engine on it's 3rd. or 4th pull. It bounced all through the engine, breaking 2 sleeves, bending valves and cracked a head. Lots of time and money lost because of a small jam nut. It was about the size of a car radio stem nut.
Personally, this whole drama should do more positive good for your business in the long run. If I didn't do all my own work, your shop would be on my short list. Take care.
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