Re: Tuning in Open Loop for Newby

[WEG1192@aol.com]

After reviewing a bunch of EPROM bins, I have a question about tuning. My 
understanding is that the tuning is for closed loop operation. But to tune, 
you set the closed loop enable temp way high to keep the ECM from entering 
closed loop. So now, are you tuning in open loop or closed loop? If open loop 
is nothing more than the closed loop tables without O2 feedback, what are all 
the open loop AFR correction vs. MAP and AFR correction vs. coolant temp 
tables for? Seems to me that these tables would interfere with proper tuning 
for closed loop operation. If you tune with those corrections applied, and 
then you drive in closed loop, seems that your tuning would be inaccurate?

Also, it was mentioned a while back that setting ignition timing advance to 
just before knock occurs at all RPMs is not always the best setting. If 
that's the case, what criteria is used as your tuning goal? Best acceleration 
under WOT? Best mileage? Etc.

Thanks
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