7747 spark control questions.

[Kevin R]

In trying to understand this a little more I have a few questions and
suppositions. Need you guys to yea, nea or just plain shoot hole thru them
for me..
Thanks.

Initial spark advance: Lets the ECM know what the dist is set at physically,
but all the bins I've checked seem to be set at 0.. does this mean those
application(all trucks) dist are set at 0 physical from the factory or have
I got what this does wrong?

Warm Bias (main bias in TC): Just so neg advance can be applied in spark
table as pos numbers!? Why is this necessary? If the dist is set at 0
physical why would neg numbers be needed in main table?

Cold Bias: So neg numbers can be applied as pos numbers in coolant(engine
temp) compensation table. I can see this, but is this table(would think so)
always active?  Then it would seem both Cold and Warm bias' are active all
the time!?

PE spark: Trying to compare this to a function in a mech dist(I know the
elect always for more specific spark control) the only reason I can see for
this is either to use lower numbers in main table for emissions reasons and
add it back when needed for acceleration or like the PE enrichment to get
some spark going faster than would happen waiting for a value lookup???


Kevin R

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