Fuel Injector Valve Phasing...

[Dave Williams]

-> These produce relatively fine (about 30 micron I believe) sprays in
-> excelently controlable patterns.  I read (in SAE?) that Ford is

 Um, yeah.  Have you had a chance to observe the injector spray patterns
with a stroboscope?

 I got a surprise when a friend hooked a strobe to his injector tester
and fired it up.  The first thing of interest was, all the different
injectors look pretty much the same, whether pintle valve, disc valve,
etc.  The second was, they all sort of dribble fuel as they open, then a
small stream, which gradually opens to a narrow angle stalactite(mite?)
looking shape, when then contracts back down to a point before turning
into mist and droplets.  The typical spray pattern was about six to
eight inches long.

 At a quick guess, probably less than half of the volume of injected
fuel is dispersed in a particle size like you're talking about.  The
rest looks pretty much like an old-time carburetor accelerator pump
shot. And most of the fuel, whether stream or spray, impinges on the
manifold or port well upstream of the valve.  Fortunately none of this
seems to matter except for cold idle and low-RPM emissions
characteristics.

====dave.williams at chaos.lrk.ar.us========================DoD#978=======
  can you help me...help me get out of this place?...slow sedation...
ain't my style, ain't my pace...giving me a number...NINE, SEVEN, EIGHT
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