Valve train Puzzle

[scottfab]

Originally Posted by LGAFF

The line manager at Mercury told me many of the race engines they tested broke cam chains related to oil starvation on the lower half of the motor at high RPM. He said people always think the chains are the weak point but its the oiling system pushing all of the oil to the top end of the motor; sudden stoppage snaps the chains.

Really sorry to see this happen. I see in the vid at 2:02 that the top chain guide in the valve cover is looking ok. Had you heard any piston slap before the event? Say at idle just after a cold start?
What oil were you using?
What mods were done to the engine if any?
This is not the worst I've see but as someone said. "it's rare".
We're ALL pulling for ya.
She's down but NOT out!