As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAKEOFF, NR 1 CYLINDER SEPARATED AT THE HEAD CAUSING ENGINE POWER LOSS. PILOT SHUT DOWN LEFT ENGINE AND RETURNED TO AIRPORT. ENGINE AND CYLINDER HAD 757 HOURS SINCE OVERHAUL WITH .010 INCH OVERSIZED BARRELS. CYLINDER TOTAL TIME UNKNOWN.