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Re: [alfa] Diesels and dollars



At 9:41 AM 5/26/04, webb.p@domain.elided wrote:
>> Nonsense, Peter---in fact, get a clue !!
>
>When you've built and installed your own home grown injection system

BT,DT, on a level which is apparently FAR beyond your comprehension !! Try
looking up the patents on the final generation of high speed teletype print
hammer throw circuits if you want to learn something about REALLY
interesting ways to make injector pintles dance !!! Such as--using 240vdc
for the opening pulse---

 as I have, you can make that statement.

You may THINK you have designed a home grown injection system, you ravings
make it appear as though the thing you have created is something that the
right to choice folks would be seriously interested in protecting !!

See below as to why you should read what's being said before you jump to an
incorrect conclusion.
>
>> In an efi spark engine, the fuel is injected and evaporated long before it
>> is lit, the duty cycle and/or injection rate of the injectors has NOTHING
>> to do with the burn rate, as it most certainly DOES in a diesel. Even in a
>> direct injection spark engine, the fuel is injected during the compression
>> stroke, LONG before it is lit.
>
>Noone said it had anything to do with it.   The statement was the higher
>the pressure the faster the fuel is delivered.

I was talking about diesels.

For EFI, that is a pattently false statement for several reasons.   First,
on an electronic injector the fuel pressure works against the pintle
increasing the opening time and decreasing the delivery, or injector
opening time.    The pressure in the manifold (port) or cylinder (direct)
offsets the rail pressure.   This is why the rising rate pressure
regulators are used in forced induction.

Ahhhh--someone who thinks that the great ignoramus, Corkshiite Bellmouth,
is God !!!

Rising rate regulators are QUITE different from MAP referenced regulators,
and are generally a crutch for those who do not wish--or are afraid -- to
junk a factory ecu and go with one appropriate for the purpose when ADDING
forced induction to a stock engine !

   The rail pressure is referenced against the manifold pressure to offset
the fuel pressure against it so the fuel can flow at a constant rate.

This is what is done with a MAP referenced regulator, NOT a rising rate
regulator !! A rising rate regulator, in fact, raises the pressure in the
rail at a MULTIPLE of the increase in MAP !!

  This is further complicated by the injector coil opening the pintle
against the rail pressure.   For low-z peak and hold injectors, the pulse
width modulation of the injector coil decreases the flow as the PWM % can
be a maximum of 80-85% before you burn out the injector or stick it open on
the field coil.

This statement is utterly nonsensical !! With a P&H injector, the impedence
of the coil is low, thus the current when the coil is first energized is
high. Sustaining this high current for more than about 1 ms would overheat,
and eventually melt the coil. Thus, the coil driver MUST limit the current
to the injector coil after about 1 ms . One means of doing this is to use
PWM to reduce the coil current. You seem to be confusing this with the fact
that if you go to greater than 85% DUTY CYCLE (injector open), you will not
get repeatable flow because of injector closing characteristics.
>
>> As for electronically controlled injectors in diesels (most notably the IHC
>> developed Power Stroke stuff), the actual injection rate IS faster than
>> with mechanical injection--because of higher pressure--which is NOT
>> generated by the electronics, but by mechanical/hydraulic pressure
>> multiplication tricks.
>
>There are factors present in electronic injector field coils that make
>that false too.   Mechanical injectors such as the Spica or CIS operate
>soley on fuel pressure.   Electronic injectors operate soley on magetism
>AGAINST the fuel pressure.   The only thing they have in common is the
>pressure against which the actual injected fuel operates.  I.E  the
>manifold or cylinder pressure.   And again, see the statement about PWM
>limits for low impedance injectors.


More absolute horse pooky, and, even more entertaining, it refers back to
the first batch of same !! Try reading the Navistar patents on their
electronically controlled diesel injection before you spout such utter carp
!!
>
>Why do people on this digest rush to conclusions without regard for what's
>being stated and the experience behind it.
>
>Sheesh
>
>-Peter

Shhesh my arse !!

The only rapid conclusion you have induced on this end is that, not only
are you incompetent, but that you haven't filtered  enough of the subject
through your overblown ego to appreciate your level of incompetence !!

Try buying a gallon of clue musk on e-bay, we have a full moon coming up,
and if you pour it over yourself on that night, it MIGHT enable you to find
and catch a clue !!

Greg
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