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The sleeves are perfect, so are the pistons, IMS bearing and 4 of the rods...
The crank is toast and is cracked. Since this happened on the track at over 7500 RPM lots happened all at once and it could have been much, much worse.
The hex is bent, but that happened after the piece sheared in half. Its easy to see that the piece simply twisted off from torsion.
The engine's throttle response is what did this.. It was unreal! The oil pump gears are huge and are very heavy, with them moving a ton of oil at those kind of revs lots of load is on this hex.. We never knew how much load until this happened.
Its all about finding the weakest links. As serious performance increases occur that weak link will continue to move from component to component and we'll continue to break things and find the limits.
Luckily this was a test engine, the first of it's spec and the Owner was so pleased that he barely cared that it failed... He knew we'd make it even better the next time around.
The chromoly hex is being made as we speak.. The engine is going back together with even higher CR and more head work with a new intake system. I think it'll easily break 375 at the flywheel..... all of that from an engine that used to be a 3.2 that barely made 215RWHP when I tore it down to apply "The Substitute" :-)
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