My car its not getting fuel what could it be?

well i just recently swaped a integra motor into a 91 civic dx witch its dual port so i had to do some wiring to make work with 4 injectors..wiring seems to be good.....the motor cranks but it doesnt start...i took out the fuel line and open the ignition and fuel wasnt getting into the fuel rail ..so i tought it was the fuel pump..so i bought a walbro 255 ..i just installed it and nothing..still not sending fuel...i changed my main fuel relay and nothing plz guys if u could help me i have invested alot of time and money and i dont want to give up...plz give me an answer thank you