As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE CLAMPS ON THE FLEX DUCT THAT CONNECTS THE INTERCOOLER TO THE NR 1 AND NR 2 CYLINDERS ARE TOO LARGE AND BOTTOM OUT BEFORE THEY REACH THE REQUIRED TORQUE OF 30-35 PSI. THE PARTS CATALOG CALLS OUT FOR A U84-270SH CLAMP OF THE CYLINDER AND A U84-260SH CLAMP AT THE INTERCOOLER. IT WOULD BE BETTER IF BOTH WERE A U84-260-SH. THIS DUCT BLEW OFF AT THE CYLINDER IN A FULL POWER TEST RUN OF NR 2 CYLINDER.