Netres availability

[Gerald Pelnar]

----- Original Message -----
From: rr <RRauscher at nni.com>

>
> Scot Sealander wrote:
>
> > rr wrote:
> >
> > > (I've been debating on whether to jump in here). One thing
> > > to remember is that on a V8 with a 2bbl TBI, it really is
> > > two separate 4 cylinder engines. The manifold GM uses is a
> > > dual plane with a divided plenum. One injector per 4 cyls.
> >
> > Could you clear this up for me?  I don't understand what you are trying
> > to say.
> >
> > Scot Sealander
>
> It was mentioned that the problem with a '747 and a 4cyl engine
> with 1 injector: was that the one injector wasn't firing often enough.
> That the one injector was firing every other plug firing. This was the
> cause of the backfiring and herky-jerky motion.
>
> When looking at the common TBI V8, the injector firing intervals
> per spark plug firing is the same. Each injector fires every other
> spark plug firing. The V8 then divides the two injectors between two
> banks of 4 cylinders. Same as 1 injector on a 4 cylinder engine.
>
> This is by the design of the intake manifold. The manifold is split
> with each half feeding 4 cylinders. Each half is feed by 1 injector.
>
> No difference in the fuel feed per injector between the 4 cylinder
> and 8 cylinder engine.
>
> BobR.

That sounds fine and dandy, but the problem is that in sync mode the 7747
uses ignition events to fire the injectors. The 4 cylinder would have half
enough ignition events to get the injectors to fire properly. 2 ignition
events per rev as compared to 4 for the 8, so a single injector would only
fire once per rev.

Gerald

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