Mechanical or electrical fuel pump

A long time ago I was taught that an internal combustion engine needs; 1/2 pound of fuel, per horsepower, per hour.
So then; 500hp needs; 500 x 1/2 =250 pounds per hour of fuel
250pounds/6.25pounds/g =40gallons per hour
40g x 128oz per g /60minutes=85 ozs per minute, for 500 hp.

the 1969 FSM lists the factory pump as
"The fuel pump should supply 1 quart(128/4=32 ounces)of fuel in 1 minute or less at 500 rpm"
The manual does not say that this spec pertains to any particular pump on any particular engine. Ergo, one could make the leap that this spec pertains to all factory pumps for all engines,in 1969.
And if that is so, then even a slanty pump can feed 188 hp at 500 rpm.
I'm not gonna make the leap that the same pump that puts out 32 ounces at 500rpm will put out 10 times as much fuel, at 10 times the rpm (that would be 320 ounces at 5000 rpm). No, I'm not suggesting that at all.
What I'm suggesting is that the mechanical pump can put out a lot of fuel, can put out adequate pressure, and both the pressure and the volume vary with rpm, perfect for an internal combustion engine.

The P4007040 small-block pump has no trouble keeping up with my 400hp plus SBM.It is rated to [email protected]
There is a BB version,P4007039, that is rated the same.
80gph is; 80x128/60=170 ounces per minute, or 100% higher rating than what the formula says you need.
Mopar says it feeds hemis.
You decide.

Ps; I converted the 80gph to liters per hour, if you need to know that; and my math says using 1qtUS = .914 liter;
80gallons x 4qts per gallon x .914conversion=292 liters/hour