Sequential injection.

[Jose Carlos Rublescki]

> > > Hi all,
> > > 
> > > While trying to develop a multiport FI system to a four cylinder
engine I
> > > figured that (obviously) a system that would drive all the injectors
at
> > the
> > > same time, or drive them in pairs is easier to do than a true
sequential
> > > system where each injector is controlled independently. What would be
the
> > > advantages of a sequential system (if any)? I'm trying to decide
whether
> > > it's worth the added complexity of a sequential system. Another
question
> > is
> > > when would be the best moment to turn the injector on (or the best
time
> > to
> > > turn it off???).
> > > 
> > > Thanks in advance,
> > > Jose Carlos Rublescki
> > 
> 
> Inject when the inlet valve is closed.  Start injecting soon after it 
> closes so that you have stopped before it opens.
> 
> Martin

Let me see if I got it right: It's better to inject the fuel when the inlet
valve is NOT open (I accept that but would like to know why). But if I
start injecting soon after the inlet valve closes than at idle (when you
inject just for a little time) the fuel would be "sitting there" for almost
two revolutions (and for a long time because the engine is running slowly).
 Because of this fact, couldn't another cylinder "steal" part of that fuel
for itself ? And part of the fuel would stick to the walls of the intake
system, wouldn't it?

If I could control when the injector is turned off so that it always turns
off when the inlet valve is soon to open than I would have the most
efficiency? Am I correct?

Why shouldn't I inject fuel when the inlet valve is already open?

Jose Rublescki