MAP data...was Re: 48 +1 and sensor data

[John_Calabrese at ENGELHARD.COM]

Well, I was going to keep my mouth shut as I don't know the "tpi" calibrations
that well.  But in the LS1 generation of calibrations(specifically 99), I found
some unexplainable spark retard under boost, knowing we didn't have knock, the
darn thing still retarded the spark.  I think it was the computer going into
some kind of safe or trouble mode where it automatically takes spark out.  It
retarded it about 7 degrees, no matter what boost level, provided it was above
atmospheric.  This tells me there is something in the cals for a positive
pressure situation, sending the engine into safe mode.  The onnly other thing is
that it might not like the frequency it is getting from the MAF (too high),
although I don't think we went above the limits, which were about 420 g/s or
11,000 or 14,000 Hz.  I think.  We were running a 4.8-L supercharged truck,
with a custom (by me) vortech installation making about 8 lbs of boost max.
(we're now getting 12 with a new pulley:)  )


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