Injector Static Flow at a Different Rail Pressure
The rail pressure injector-size says it does not cover. An injector is an orifice, so flow follows the SQUARE ROOT of the differential - pressure is a weak lever, needing 4x the differential to double flow. The trap is the fuel system: a return system's manifold-referenced regulator holds the differential constant under boost, but a returnless system holds the RAIL constant, so 15 psi of boost on a 43.5 psi rail drops a 550 cc/min injector to 445 - 19% LESS fuel exactly when the engine wants more.
Formula and source
flow_new = flow_rated x sqrt(dP_new / dP_rated); returnless dP = rail - manifold pressure, return (manifold-referenced) dP = the regulator's base setting; lb/h = cc/min / 10.5.
Orifice flow scaling with the square root of the pressure differential - public physics, no table and no fitted constant. The cc/min to lb/h factor matches the landed injector-size tile (gasoline about 0.72 specific gravity).
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