it really depends on how much fuel your engine uses, but let's see what 80's are capable of....
at 100% duty cycle, you'd have 6 injectors pushing 80 lbs./hr. = 480 lbs./hr (assuming optimum performance of the injectors)
If gasoline weighs 6.073 lbs/gallon, that's 79.038 gallons per hour.
79.038 gallons = 299.16 liters.
Your injectors are capable of flowing 299 liters per hour. If your motor can gobble up all that fuel.
If you only run at max of 80% duty cycle, then your motor will be consuming 239 LPH of gasoline.
You can cheat a little by increasing voltage to the pump. The more volts that go to it, the bigger the flow increase.
based on the numbers above, I wouldn't plan on pushing those 80's to 100% IDC with just one 255 LPH pump. Remember these are theoretical numbers too. The real world includes variables that aren't accounted for in my calculation above. Maybe a 340 LPH, 416 LPH, or double-pumper is in your future!!!
Do you have a powerlogger or a way to measure your injector duty cycle? Better safe than sorry as far as fuel supply goes.