EST observations (kinda long)

[Tedscj at aol.com]

In a message dated 2/23/99 1:04:38 PM Eastern Standard Time, ludis at cruzers.com
writes:

I wrote originally:
> > You see that these are all equally spaced.  The P4 document states that
the
>  > ECM looks for the 'falling edge' to determine a reference pulse.  I have 
> read
>  > and heard that the difference between an HEI module and DIS module is
that
>  > this signal is inverted.  So maybe a DIS .bin looks for a 'rising edge'?
>  > Either way it can't be much of a problem since even an inverted signal
has 
> a
>  > 'falling edge'.  You might just have to adjust the base timing to make up
> for
>  > the pulse displacement caused by the inversion.

Ludis wrote: 
>  The problem is that the other edge may "move around" at different RPMs.
>  

Based on what I recorded (the signal going from the Module to the ECM), it
does not seem to move around at all.  The distance from the rising edge to the
falling edge and then to the next rising edge, and so on and so on....  Is
always the same at a given RPM.  This is true for the signal that goes from
the Module to the ECM.

As for the EST signal that goes from the ECM to the Module... The falling edge
is constantly moving.  Some  times it is closer to the previous rising edge
(low RPM), and sometimes it is closer to the following rising edge (high RPM).
I believe this represents dwell.  If THIS signal is inverted, then it would be
fairly difficult to get a DIS module working with a Distributor typ .bin as
the Dwell signal from the ECM would be interpreted as the Advance timing by
the module, and visa versa.


Ludis wrote:

>  (Question:  Are the SyTy and Sunbird distributor or DIS?)
>  

SyTy and Sunbirds use a dirtributor.  I would like to adapt DIS to work with
their .bins.