O2 sensor idea

[Bruce Plecan]

----- Original Message -----
From: Ord Millar <ord at aei.ca>
To: <diy_efi at efi332.eng.ohio-state.edu>
Sent: Tuesday, April 20, 1999 1:44 PM
Subject: Re: O2 sensor idea

If you look at the Injector Flow Bench it mentions using a piezio elec
device for
"looking" at the injectors response.  So using a dual trace scope would give
ya the answers about actual on times, for "on" time.
   In the past I've posted some fuel tables, hoping to shed some light on
this so you could use a generic table, and at least have a starting place.
  Depending on injector, at anything less than 2 msec the injector maybe
rather erratic (saturated style injector), so be careful at looking in this
area.
  If your looking at kinda averaging to get it right, I'd visit the past
mention of driving the injectors at 106% of crank speed.
Bruce

> This is probably an often asked question, but here we go:
> If I have an efi system using and air mass meter, and I can build myself a
> table of injected volume / pulse width (by flow bench or other means),
then
> isn't it possible to calculate A/F pretty closely?  It might not be
> instantaneous, but over the span of a half dozen or so intake events
> wouldn't the average come out pretty close?
>
> -----Original Message-----
> From: CEIJR at aol.com <CEIJR at aol.com>
> Subject: Re: O2 sensor idea
> >Another $.02
> >Assuming that changes in pulse duration result in linear changes in fuel
> >delivery are OK for rough initial setup. As noted in prior posts, all
sorts
> >of other variables come into play. Unfortunately, in addition to VE
> >differences, etc., the fuel flow is not exactly tied to pulse width, due
to
> >the variation in percentage of time spent opening and closing. So, it is
a
> >rough estimate for initial setup, but not good enough for tuning.
> > Charlie Iliff