Electronic AFM adjustments & large injectors.

Marcel marcelb at casema.net
Sun Feb 28 23:11:19 GMT 1999


Ok, I've been reading in the archives a bit, researching on increasing
fuel capacity by adding larger injectors, which I plan to do to
accomodate a turbo project.

I read AFM voltage output is proportional to natural log of airflow.

Well, a little mathematics tells me, if you multiply airflow by
.91 across the board (lying to the ECU to compensate for 10% larger
injectors), AFM voltage will have to decrease with a constant
(ln .91) amount across the board.

So, if I add some kind of offset control to shift AFM voltages
down a bit, am I right to conclude this gives me a LINEAR decrease
of the airflow reading across the board, which will decrease
injector pulsewidth linearly, exactly compensating for bigger
injectors or at least better than spring tension tweaking?

Just a brain fart from a newbie who has been reading a bit :)

Marcel



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