As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ON TAKEOFF ROLL, PROP RPM DROPPED FROM GOVERNING SPEED OF 1700 RPM TO 1500 RPM. UPON ROTATION ,THE PROP RPM GRADUALLY RETURNED AND STABILIZED AT 1700 RPM ONCE AIRBORNE AT 20 FEET. MAINTENANCE REPLACED THE PROP GOVERNOR WITH A NEW STYLE GOVERNOR P/N 8210-410 AS PER PRATT & WHITNEY S/B 14260R1. THE NEW STYLE PROP GOVERNOR HAS A RE-DESIGNED OIL PUMP TO INCREASE DURABILITY. PART TC: 1,445.