The thing with the 450 is flow drops off a lot at higher pressures, which you would need for the injectors to flow. So you'd either need what the OP has or get bigger injectors.

 

Not sure if it was just a high reading dyno dynamic or he didnt tell me what else he has, but I have a buddy that says he only has one 340lph fuel pump and ID1000 and made 570+whp on E85.

 

Sorry I'm still putting the finishing touches on the app so not all of the information is shown. The X represents fuel demand using BSFC that I defined in a different page in the app. In this case I used BSFC of .75 which is typical of E85 and the + Represents fuel demand using AFR, and in this case 11.8:1 for gasoline.

The Y axis represents total fuel flow in pounds per hour. The lines on the graph itself represent flow values that have been recorded at various pressures. Most are third party measured.