What was found
(CAN) A/C RETURNED TO YYC DUE TO INSUFFICENT NR 1 ENGINE EPR READINGS. CREW REPORTED ON CLIMB OUT THROUGH 12,000FT. ENROUTE FROM YYC TO YXX, THEY WERE UNABLE TO ACHIEVE ENGINE PRESSURE RATIO ABOVE 1.92 ON NR 1 ENGINE. CREW STATED LARGE THROTTLE STAGGER REQUIRED TO ACHIEVE 1.92 EPR & THAT NO LIMITED FROM ADVANCING FURTHER BY MAX EGT. NR 2 ENGINE INDICATING NORMAL READINGS, BOTH ENGINES HAD ANTI-ICE ON SINCE TAKEOFF. MAINT CONTROL ADVISED A/C TO RETURN TO YYC. A/C CIRCLED TO BURN OFF FUEL THEN LANDED WITHOUT INCIDENT. MAINT INSP DURING BORESCOPE FOUND 'SHINY PARTICLES' THOUGHOUT COMBUSTION CANS & TURBINE AREA. THEY ALSO NOTED SOME OF HPC BLADES ON C7 WERE CURLED SLIGHTLY AT LEADING EDGE TIP & SOME HAD NO G