Re: 88 quad-4

[Shannen Durphey <shannen@grolen.com>]

cwagner@info2000.net wrote:
> 
> On 24 Jan 00, at 20:54, Shannen Durphey wrote:
> 
> > You can use the turbo sunbird/syclone calibration in that one, and use
> > Promgrammer for editing.  Unless you've decided that you want to use
> > the 2.3 cal.
> > Shannen
> >
> 
> What about the turbo and related stuff on the chip?  I know about
> the 1/2 bar map setting.  What else would I have to do?  The
> engine I am going to put it on is going to be naturally aspirated.
> Also, you stated I would have problems with the tpi code, what kind
> of problems were you talking about with the dwell, I thought the
> ignition module took care of the dwell.  That is unless you are
> talking about something else.


With the dwell/timing output being the deciding factor for the
calibrations, IMO, here's what I've seen.
The timing output from the DIS Q4 calibration will be 30 degrees
advanced when compared to the Sunbird cal.  The DIS  REFerence signal
is delivered 60 degrees BTDC.  The dizzy REF signals are treated as 90
degrees advanced, as determined by watching scope patterns.

The 4 cyl DIS EST pulse to the module is 90 crank degrees high, 90
degrees low.  The DIS module has 2 coils which are both connected to
ign. voltage giving plenty of time to charge before firing.  Based on
scope readings, it looks like DIS EST is for spark timing only.

Distributor module handles dwell when the bypass mode isn't
activated.  In bypass mode, the dizzy calibration produces a varying
EST signal which is around 60 crankshaft degrees firing time, 120
degrees charging time as I'm measuring it.  The dwell calculation uses
voltage, crank acceleration, max and min dwell periods and more to
determine optimum dwell time.  This is something the DIS cal does not
appear to do.

In order to provide maximum spark, you'll need to make the DIS EST
output compatible with a single coil by changing the high/low times of
the signal.  This means hardware to modify the signal, or software
changes to produce the correct signal initially.
fuel maps, 1+2 bar switch, & other changes, I haven't looked into.
Shannen
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