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Grayhawk,
Thanks for the link. I have been reading the Cafe Articles.
I realize that the Prism will have electronic ignition, but the ignition
timing will be controlled by measured intracylinder pressures. This
is very different from an electronic ignition that uses an advance curve that
depends on RPM and MAP and ignores the effect of mixture on effective
timing.
----- Original Message -----
Sent: Friday, January 04, 2008 7:55
PM
Subject: [LML] Re: Electronic
Ignition
I have been thinking a little bit about this issue. I would like
to add my 2 cents
and see what others (particularly Adkinson and Braly) have to say
about this issue.
Doug,
Go here:
and read Ignition Dynamics I, II & III.
20 or 25 Degrees BTDC (depending on compression ratio)
provides a reasonable compromise for standard flying at 75%
(plus or minus a bit). The timing makes a bigger difference at
higher altitudes where NA engines are operating at reduced power enforced by
lack of MAP. The EI also makes a big difference in starting and high
power operations - like take off.
If the PRISM system ever becomes available, it will have an electronic
ignition.
Scott
Krueger AKA Grayhawk
Lancair N92EX IO320 SB 89/96
Aurora, IL
(KARR)
Pilot not TSO'd, Certificated score only >
70%.
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