Injector Math

[Walter Sherwin]

Having destroyed
>more than one turbo engine with lean mixture at max power output have begun
to
>suspect that the injector assumption of .55 BSFC may not take into account
>enough internal losses or necessary cooling effects when the system is
really
>working.
>
>Charlie Iliff


Absolutely correct!   The whole basis for controlling fuel mass delivery is
in fact "air mass delivery".  The "best" way to model what your fuel
injection needs are,  is to............1) determine what the peak airflow
mass rate through the engine is, .................2)  calculate what the
fuel mass flow rate should be at say 11:1 A/F ratio
(mass),................3) divide the net fuel rate by .75 to compensate for
assorted losses, and driver characteristics,.............4) divide by the
number of cylinders to get the approximate size of the most applicable
"port" injector, and..............5) pick the "next sized" injector which
satisfies both your electrical and mechanical needs.

Walt.