Re: Turbo V6 Tuniing continued + Benchtop ECU

[Barry Tisdale <btisdale@cybersol.com>]

Did some chipping on the 7749 on the bench just now, attempting to change
tables from 29# to 40# injectors:

EGR enable temp (@$6CD) = raised to max (therefore, never active)

Injector Flow Rate (@$328)= Zeroed (from 4.9 Gal/Hr)

BPC vs EGR = zeroed table *except* for leftmost entry (@0% EGR):
(@$40E)      this was set originally @ .108 for BG's 10/1 chip
             using 29# injectors - changed to 29/40 * .108 = 
             .081

Injector pulse width at 1000 RPMs on the benchtop went from 3.2ms to 2.4,
which is exactly as expected from the above changes.

So:  -The Injector Flow value indeed is not used by the ECU.
     -Changing the BPC vs EGR seems to be the equivalent of a Injector Size
                        constant.

If you had a decent running chip and merely changed injector sizes, would
you not change this (BPC vs EGR) *first*, and then do your fine tuning with
the VE tables, etc?  I'm assuming linearity to be the same between
injectors, which may not be the case, but its a place to start.

Opinions, please - Barry
             
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