Tuning Eproms (was ECM 1228746 Help)

[WEG1192 at aol.com]

In a message dated 08/14/2000 3:19:55 AM Eastern Daylight Time, 
WEG1192 at aol.com writes:

<<  found this ECM #1228746 in Ludis's site and it is listed as using the 
same circuit 
 board as the 1227747 ECM. I also found a bin file for it in the DIY incoming 
 ftp. But I can't find the pinout diagram. Does it use the same pinout as the 
 7747 if it has the same circuit board? >>

Anyone?

Also, disconnected my O2 the other day and drove around to see how "off" my 
EPROM was. The voltage on the disconnected O2 was never below 0.7 volts and 
sometimes up to 0.9 volts. And this was without resetting the BLMs back to 
128. I bet if I take power from the ECM and do this again, it may not run at 
all. Any comments?

Also, concerning tuning EPROMS. I can see why you would want to tune the fuel 
to get the BLMs to 128. You are basically getting the mixture right on to 
where the O2 is a redundant sensor. But the timing seems to be a different 
situation. Since there is no timing equivalent of the BLM (other than the 
knock retard safety device), is it possible that GM sets the timing where it 
is to minimize emissions such as NOx at part throttle? Maybe do-it-yourself 
tuners should concentrate on timing at WOT only since its a free for all 
there, i,e, emissions be damned. Or do I have too much faith in GM's talents? 
Are you DIY tuners changing timing strictly to get the most performance out 
of your engines and discarding emissions concerns, or are you saying GM is 
doing a half arsed job in both timing and fuel?
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