triggering an HEI module

[Programmer]

What do you mean ? It's the pick-up that rotates in relation to the pole, so
the trigger changes it's position at advance.

Lyndon.
----- Original Message -----
From: Bruce Plecan <nacelp at bright.net>
To: <gmecm at diy-efi.org>
Sent: Friday, March 09, 2001 7:01 AM
Subject: Re: triggering an HEI module


>
> IF that were true there would be  no timing change reguardless of how the
> reluctor is wired up.   What you mention is what GM teaches, which ain't
the
> truth on that item.  Sorry to crush you with the horrors of the truth.
> <g>...
> Bruce
>
>
> > The signal into an HEI module is far from a sine wave. It
> > looks like a slowly rising voltage which rises faster and
> > faster as the pole pieces come together.  Just as the poles
> > pass peak, the voltage very, very  quickly reverses polarity
> > to about the same but opposite voltage.  Then it decreases
> > like a mirror of the first part.  Then it crosses zero and starts
> > climbing again for the next pole alignment
> >
> > The spark is triggered by that very rapid voltage reversal at
> > the peak pole alignment.  The amplitude varies a lot with
> > speed, but the point of reversal is consistant.  Bruce Roe
> >
> > On Thu, 8 Mar 2001 19:59:23 EST Tedscj at aol.com writes:
> > > Hi,
> > > Has anyone tried to determine what type of signals will trigger an
> > > HEI module?
> > > To be more specific with what I want to achieve:
> > > I have a little foreign four banger with a really pitiful points
> > > ignition.  I
> > > was thinking of converting it to GM DIS as a first step towards
> > > full-blown
> > > GM-EFI.
> > > The problem is that the only after-market conversions from points
> > > available
> > > for this car are to 'optical sensor' ignition, which will result in
> > > a square
> > > wave signal from 0v to 12v.  I know HEI modules (and DIS) are
> > > looking for a
> > > sine wave.
> > > Does anyone know if a square wave will trigger the module?
> >
> >
> > ________________________________________________________________
> > GET INTERNET ACCESS FROM JUNO!
> > Juno offers FREE or PREMIUM Internet access for less!
> > Join Juno today!  For your FREE software, visit:
> > http://dl.www.juno.com/get/tagj.
>
> --------------------------------------------------------------------------
> --
> > To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
> > in the body of a message (not the subject) to
majordomo at lists.diy-efi.org
> >
> >
>
> --------------------------------------------------------------------------
--
> To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
> in the body of a message (not the subject) to majordomo at lists.diy-efi.org
>

----------------------------------------------------------------------------
To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org