Fuel Injector Valve Phasing...

[Robert Gallant]

>  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.

I have some photo's, taken by John De Armond, of two Rx7 injectors, 280 Z 
injector, and a GM injector.  All are port injectors (not throttle body), and 
they have drastically different patterns.  The GM injector (don't know what it 
is from) flows like water from a garden hose.  The Z and Rx7 injectors have a 
wider spray pattern which is "misty".

When I get a chance, I'll scan them into my web page.

Later

Rob
gallant at oasys.dt.navy.mil