As far as I know PIC is simulating the GE engines. But what differece is between the EICAS display with GE or PW engines?Thank youMatthias

With PW, epr is also displayed on the primary EICAS. GE's do not display EPR, they run the engines off of N1. With RR engines, which are on the 757, epr is displayed on the primary, and N3 is indicated on the lower EICAS, just a little bit of trivia for you.

As already said, GE has 4 engine indications.PW adds a fifth EPR, and RR adds a sixth N3.And to get to the real small things... PW has an oil pressure upper limit. RR have a 'marker' on the virbration indicator, above which the screen will turn on if blanked.