Injector constants, Base Pulse Widths, VEs, LV8

bruce plecan nacelp at bright.net
Mon Feb 9 00:12:58 GMT 1998


Continuing:
Sometimes you can make a FP adjustment and the engine responses
perfectly.  If you increased the fuel pressure, and the engine runs
better, that means one thing, it was universally lean.  Now you'll 
quickly reach a point when changing it doesn't seem to make much
of a difference, and then performance falls off quickly.  When ya
try to add addition fuel (more than what is needed) the ecm just
leans things down,  so the BL changes.  When the engine goes to
WOT enrichment it glances over at the BL and if it's low (less tan
128), then it will reduce the injector open time.  So if you want to
richen WOT then you have to lean the tables down so the BL
is right, or change the WOT AFR.  Conversely  to lean out the
WOT raise the VE table entries, or lean down WOT AFR..
  If you can't change the TPS enrichments then try setting
the VE high and low, (to try having different BLs), then you can
get this BL to work for you, as an enrichment during TPS
transisitions.  The reason this works is that the ECM will
start moving the IAC counts around.
  When tuning remember the IAC is a vacum leak..  Less
is better, as far as I'm concerned.
To quote from the OTC Manual
 " LV8, Filtered Load Variable (LV8),  In the filtered load variable
mode, a number will be displayed that is proportional to the 
measurement of the amount of air being displaced per cylinder.
The filtered load variable replaces the MAP sensor in some
applications."  So a MAF reading is grams/second, and a LV8
is a number that is a proportion.
  So in a MAP set of calibration tables you have VE tables,
and in a MAF you have LV8.
  Both have a series of TPS %s to enable WOT
  Both have a correction for WOT enable, it may be a VE
adder or % increase in injector timing.
  I hope this shed some light on things for at least a few folks
if ya have more questions e-mail me, and I'll try to figure out
a posting about it.
HTH Bruce     I would urge all cone shaped hat wearers to
                       join in with gathering funds to save the 
                       easter seals.
PS On a serious note does anyone know anything about
making technology accessible for the handicapped other
than the law, ie corp programs, please e-mail me?..
PSS  I invite ya to comment if in error with the above.........



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