Injector Max Horsepower Capacity

The inverse of the injector-sizing tile: the maximum power an injector set supports - HP_max = injector lb/h x n_cyl x duty / BSFC. Eight 31.25 lb/h injectors at 80% duty and BSFC 0.50 support 400 hp; the SAME injectors on boost (BSFC 0.60) fall to 333 hp, why a richer tune caps power. Enter flow in lb/h or cc/min (lb/h x 10.5 = cc/min). 80% max duty avoids a lean fuel cut. Port injection, entered BSFC; not rail pressure or DI. A tuning aid; the measured fueling and the tuner govern.

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Formula and source

inj_lbh = flow (or cc/min / 10.5); total_lbh = inj_lbh x n_cyl x duty; hp_max = total_lbh / BSFC.

The fuel-injector-sizing relation solved for the supported power, the inverse of the injector-size tile, a standard tuning-reference result, by name.

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