7749 guru needed....

[Barry Tisdale <btisdale@cybersol.com>]

Gentlemen -

I'm in dire need of some assistance w/ my current project, bigger cam &
heads on my Sy.  Problem, naturally, is reduced vacuum @ idle & part
throttle, so's I've got to make some chip changes.  I've got 3 bar chip/MAP
sensor & using Promgrammer98 & have complete ALDL data logging & reading
setup.  I've done some chipping, sucessfully changing such stuff as idle
speed & EGR disabling, but I'm coming up empty here.

I thought I'd go about it slow & easy, learning as I go.  First thing I
want to tackle is the idle, now about 14"Hg (50-55kPa), @ 750 RPMs.

Integrator at idle, warmed up & in closed loop, reads high 80's.  Means its
cutting fuel, meaning (to me) tables specify too rich an A/F ratio, VE
being too high.

Been working w/ the F29 table (the one @ 0476), VE vs. RPM & MAP, Closed
Throttle.  Seems to me, the numbers @ the upper left of the table are the
critical ones here, 600 & 800 RPMs @ 20-30% MAP.  I'm assuming that the MAP
figure is given in percentage, and idle is gonna be right down at the
bottom of the percentages, so these four cells are the important ones.

I would expect reducing these figures, (VE) would reduce fueling, and cause
the Integrator values to rise.  However, I can take these 4 numbers right
down to zero and the Integrator readout is unaffected.  

After I do the idle, I've got to do off idle, which is *really* terrible w/
the new cam - stumbling, backfiring & knock on light throttle application
(O2 is in double digits).

BUT - gotta learn to walk first; there's no cause & effect relationship w/
my idle correction attempts, so I'm not going to attempt to correct
anything else until I understand how to do things here.  

Any suggestions from the gurus out there?  I'd really appreciate any
assistance w/ this!

Thanks - Barry
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