FLT CREW OF B763 DISCOVER RECENTLY REPLACED ENG NOT PERFORMING TO SPECS. EVENTUAL DIAGNOSIS DETERMINES THAT COMPUTER PERFORMANCE PARAMETERS FOR THE ENG HAD BEEN SET TO THOSE REQUIRED FOR ANOTHER ACFT TYPE.

Narrative

WE FLEW THIS ACFT ON ITS SECOND FLT AFTER THE R ENG WAS REPLACED. THE TKOF FROM SFO WAS A PACKS-OFF; MAX THRUST TKOF DUE TO OUR GROSS WT. EPR WAS CALCULATED BY ACARS AND THE TMC TO BE 1.57; WITH AN N1 OF 104%. ON INITIAL TKOF ROLL; AFTER PUSHING THE EPR SWITCH; THE L ENG SETTLED AT 1.57 EPR; 104% N1. THE R ENG SETTLED AT 1.54 EPR; 100.7% N1. THE FO TRIED FINE-TUNING THE THROTTLE; AND BY THEN WE WERE AT 80 KTS. I TRIED PUSHING THE R THROTTLE FORWARD TO GET THE REQUIRED VALUE OF 1.57 EPR; BUT THE THROTTLE WAS ALREADY AGAINST THE FORWARD STOP. THE AIRPLANE WAS ACCELERATING NORMALLY; SO I DID NOT DEEM IT NECESSARY TO DO A HIGH SPD ABORT FOR AN EPR DIFFERENCE OF .03. WE REACHED V1; VR; V2; WITH PLENTY OF RWY LEFT; AND HAD A NORMAL CLB. HOWEVER; CLBOUT EPR WAS 1.67 ON THE L ENG; BUT ONLY 1.62 ON THE R. IT WAS THEN THAT WE NOTICED THE DIFFERENCE ON MAX AVAILABLE EPR (YELLOW TICK MARK) ON THE EPR GAUGE. AT CRUISE; THE EPR'S WERE MATCHED; BUT MAX AVAILABLE EPR WAS 1.70 ON THE L ENG AND 1.63 ON THE R. WE SENT AN EVENTS RECORD TO MR X ON CLBOUT; ALONG WITH AN ACARS MESSAGE. IT WAS NOT UNTIL APPROX 5 HRS LATER THAT DISPATCH CALLED US TO TELL US THE REASON FOR THE DIFFERENCE ON EPR READINGS. THE R ENG WAS PROGRAMMED FOR A B747-400. WE WERE ALREADY ON THE ETOPS AREA (OVER CANADA) AND WE DECIDED IT WAS SAFER TO CONTINUE TO ZZZZ.