In a message dated 96-11-26 17:30:44 EST, Dave_Clement-LDC009@email.mot.com
(Dave Clement-LDC009) writes:
<< At Wide Open Throttle the computer is not operating closed loop. It
reverts
to look-up tables to decide on injector duty cycles and timing based on a
subset of the sensors. >>
Very interesting, though this does conflict with the programing of the 20
Eproms.
The computer would have to have multiple sets of tables to taylor to each
different
driving situation. Your explanation makes perfect sense to me, but doesn't
explain
why fuel injector pulse width is "set" to grandma's driving, then
reprogrammed to
Mr. Leadfoots driving. My time's at the track have been close to a half
second slower
when my wife has been driving it all week, then back up to speed when I 've
been
punchin it all week. This means that a table, that is specific to that
particular engine,
would be established at WOT. Who knows? As for the MSD,Crane,etc giving a
better idle
due to a multiple spark, I tend to doubt that it is needed on these motors.
Multiple spark
is needed for cams with lotsa overlap (40+) up to 3000rpm then the spark
becomes
one big spark thereon. The Crane has the option to disable the multiple spark
below 3000rpm
which is the option I use. The rev limiter also confuses the SBEC by removing
spark, and if the
stock or emission legal cams are used, you don't ever have enough
overlap(shitty idle) to require a
multiple spark below 3000 rpm. But in doing the job as a burner of excess
fuel, I'll admit nothing
gets by my chambers unburned, making this Dak pass emissions with an A+.
Thats why I can't
seem to picture the aftermarket units "Controlling the timing" and the SBEC
sitting pretty...penny
for your thoughts...NOW, will an aftermarket ignition cure
detonation??????????
Kuk
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