7747 vs 8062

[Reid Bishop]

As some of you know, I've been struggling with a finicky '89 4.3 with
Edlebrock Manifold, Cam, and other tricks dropped into a 85 Cherokee.  I
originally had a 1228062, but the folks at Howell assured me that their 4.3
TBI Engine Harness would _not_ work with the 8062.  I then picked up a 7747,
and dropped in the factory 4.3 Calibration (AKDX).  Worked ok, but had a
horrible rough spot at 1500-2300 at low MAP pressures.  I tried tweaking the
VE tables and spark, but was never able to get it to run 'right' at these
low RPM/MAP areas.

Last night, I decided to try the 8062 as opposed to the 7747.  The 8062 has
the ANKB calibration.  Well,  the folks at Howell were dead wrong.  As far
as I can tell, this ECM/calibration is MUCH better.  It runs better on these
recent cold days, and doesn't seem to have the stumble/misfire it had
before.  It has a better low end, with a much more responsive torque curve.
I also have the sneaky suspicion that my mileage is going to be much better
with this calibration.  I'll know in about a week or so.

Does anybody have any info on the 8062?  It was only used on 88-91 S10
trucks, even though they also used the 7747 in '90 and '91.  I haven't yet
gotten ALDL recordings from this ECM/calibration, but will get them tonight.
Is the ALDL output the same as the 7747?  I know the definition for this ECM
is different, so I'll have to buy a new calibration module for TunerCat,
unless somebody has the table locations pinned down in the 8062.

Stumped... but happy!

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