Turbo Tuning

[turbo31 v6]

Let me first say where my brain resides, I understand GM digital fuel 
injection systems including sensors and controlled devices etc.  I also have 
a good background in engine mechanics rebuilding stock and high performance 
engines.  I also use and comfortable understand hex and decimal reading 
systems for our bins, being able to make changes and burn the EPROMs.  I 
Also understand GM calibrations (that was fun) regarding tables, calcs and 
usage strategy.  The tuning tips provided by such great guys such as ECMNUT 
and Bruce P were excellent reading and helped fill the gaps as well as 
confirm previous areas of understanding.

Now, the work that I am doing (and I feel that my ground breaking and 
learned results shared with the list here will help enlighten many who are 
coming up the ranks of being tuners) is to change the tables in my bin to 
accommodate the mechanical and external changes done to this engine.  I have 
a set of high performance aluminum heads, more aggressive supposed computer 
friendlier cam upgrade, 29 lb injectors and a 39 lb hr turbo, low 
compression pistons and a well done performance rebuild to the rest of the 
engine.  I will run pump gas for now but 100 octane will later satisfy the 
need for more speed, later.

The good news for those willing to help me is I know the locations of all 
fueling and timing tables and calcs as well as single items such as 
disabling EGR etc (big sigh heard ;-).  So, with EGR, PE, AE, Purge, Boost 
mult tables (no boost till VEs done) and associated flags disabled, on to 
the work.  Right off with the large injectors, the stock turbo chip will 
need to be re-worked, and the claimed single values for injector rating 
GL/HR single injector flow rate and SEC/GM product of injector flow rate and 
fuel calculation base constant for single fire were changed right off with 
little help at all.  Now the change for GL/HR was easy to convert but, 
SEC/GM? I assume seconds/gram of fuel (what)?  Taking this number down 
accordingly to the injector size increase did not help and I may try to go 
the other way (increase).  Next is the infamous VE tables, 3 of them, F29 
(TPS >/= to 2%) base VE for 600 to 4000 rpms and vac to boost load ranges, 
cool.  Then the F29 Extended table for TPS < 2% good again.  Now knowing the 
big F29 is for main driving and the Extended F29 for fine tuning idle fuel I 
am left with….F30 VE vrs RPM for?  For this table, RPM is below idle to near 
read line and is a one liner (not 3D table) that I am not sure how to use, 
and which VE first to tune.  Can it be that the F30 is a bulk change (maybe 
get the injectors closer right off?) and the F29s for the rest?

Thanks for all the help in advance.

Jesse

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