DIS with 749.bin success

[Bruce Plecan]

-----Original Message-----
From: Mike Pitts <mpitts at netspeak.com>
To: 'gmecm at efi332.eng.ohio-state.edu' <gmecm at efi332.eng.ohio-state.edu>
Date: Friday, March 05, 1999 4:13 PM
Subject: RE: DIS with 749.bin success


>Can anyone tell me what kind of signal the HEI
>module in the 4.3L Chevy distributor outputs?

The interface of the wire wires for the distributor/DIS are all the same.
Blk/red ground (low) Brn/Blk EST, White, Purp...
5v square wave.  It's just the matter of timing to select from one to the
other.

In the DIS, there is a "sync" to the Ignition Module (not to be confused
with
a sync lead to the ecm for SEFI).  There as I have been corrected, are two
sytles
of triggers for the DIS, Hall effect, and reluctor.

>I would look for myself if I could, but I don't
>have an o'scope.  :(
>I'm wondering if I can just use the signal that's
>already there for DIS, perhaps altered/buffered by
>some sort of cheap/simple electronics.
>Bruce, I'm sure you know. :)
>This could save some time by avoiding the fabrication
>of the mechanics/electronics of the distributor.

To run DIS, for most folks will require some fabrication.  However on your
vortec there is a later timing cover that accepts a DIS trigger.  While your
engine is apart might be the time to investigate.  This setup is hall effect
Bruce

>BTW: Does anyone know of a decent place to find used
>o'scopes for sale, cheap?
>Thanks,
>-Mike