Netres availability

[WEG1192 at aol.com]

In a message dated 8/22/2001 3:46:07 AM Eastern Daylight Time, 
Sealand at clarityconnect.com writes:

> Because the second injector output is unused, he is missing half the
>  fuel.  If he increases the fuel, one cylinder will get a lot of fuel,
>  and one will get short-changed.  This arrangement suffers from poor fuel
>  distribution.  In short, don't use a 747 on a 4 cylinder, unless you use
>  both injector outputs. (And use them correctly.)
>  
>  My apologies for the alignment for the timing diagrams.  I used both
>  tabs and spaces, so it may take editing to get it lined up like I drew
>  it....  
>  
>  Scot Sealander

This is what I was trying to say all along. I didn't think it needed this 
much of an in depth discussion though. To remedy this problem, could he 
connect the one injector in parallel with both injector drivers? Since the 
injector drivers pull to ground, I don't think it would hurt an injector 
driver if it was grounded by another driver.

I think it all gets back to how many times one injector can be fired on an 
engine. I think the V6s and V8s use two injectors because there is not enough 
time to fire a single injector for 3 or 4 firings per revolution. A V8 has 8 
poles on the reluctor. The dist shaft turns at half the speed as the engine. 
So in a single revolution of the engine, you would only get 4 ref pulses. But 
with a 7747, two injectors are fired alternately, so ONE injector only gets 
fired twice per revolution.

Now getting back to a 4 cyl, you only get two ref pulses in one rev from the 
dist. If only using one driver from the 7747, you will get one injector 
firing per rev, since the other driver fires but isn;t hooked up. This means 
that in one rev where you have two intake strokes, one cylinder will get a 
shot fo fuel and the other won't. This is what I meant by two cylinders 
tagging along in a complete cycle of the engine ( 2 revs for a 4 stroke 
engine). Now if the two injector drivers can be connected in parallel, then 
he'll regain the lost injector firing and he should get two firings per rev, 
which is the same number of firings that a single V8 injector gets.  Just my 
0.02. JW
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