Re: EPROM tuning head start

[WEG1192@aol.com]

Some thoughts on this (7747) tuning methodology. From the tuning tips it 
appears that spark timing is the first to tune since the BLM can keep the car 
running even without a "perfect" fuel map. If you don't have a scanner or 
Diacom, could you use a DVM on the TPS, a vacuum gauge and a tachometer. Do a 
run and keep the vacuum and tach steady with throttle (TPS). Note TPS value 
that this takes. Advance timing in the spark table corresponding to the 
vacuum and RPM. Do run again and watch for a significant increase in TPS to 
keep car at same RPM and vacuum. This would indicate knock retard I believe. 
Back off timing and do run again to make sure of max. timing before knock 
retard. Do all cells of BLM this way, assuming the BLM cell boundaries are 
known. Then, drive car until all BLM cells have had a chance to settle in. 
Then note the value of each BLM cell away from 128. Now, is there a way to 
correlate the amount the BLM is away from 128 to the amount needed to adjust 
the VE vs. RPM vs. MAP table? If the goal of tuning is to get the BLMs at 128 
or slightly smaller, why not let the BLM tune for you and get you homed in 
much faster? If the BLM is at 120 in a certain cell, why not remove a 
specific amount of VE from the table to increase the BLM by 8 points? If this 
is possible, anyone know how much VE corresponds to one point in the BLM? 
This may vary by RPM, MAP, etc., so any comments on the concept? From here 
check the BLMs once a week and adjust VE to move BLMs back to 128. Tune WOT 
standard way.
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