I am going to hate myself for this in the morning, but:
It seems Scott is the only contributor who has actually flown with EI--the
rest have strong opinions based on whatever and seem to blindly advocate iron
chunks strapped to the top/back of aircraft engines that disappeared from
the rest of the internal combustion community decades ago. Well:
1. I have an O-320 with a single LSE system that I have flown
for about 1000 hours over 15 years and love it--I have replaced parts of or the
whole mag several times over that period; no troubles with the EI. I also
have a timing readout and dial-a-detonation pot that allow me to observe the
actual EI timing (assuming inst error equals zero) and vary as I wish. The
results over all phases of flight have been interesting, not catastrophic!
I have used this plane (LongEZ, built by me and first flown in '85) as an
airborne test bed as I planned and built my LIV.
2. My LIV has a TSIO-550 with nothing extra on the accessory case--no
vac pump, no stby alt, etc--so I removed the mag drive gears when the engine was
built up by Monson and have a dual LSE system with a three power source
electrical system (2 bat, 1 alt). I also have a timing readout for
each LSE in the CP, along with a pot for each to vary the ignition profile
in flight. I should fly this spring, if I ever finish the body
work...
So why this config on the big plane? Well:
1. LSE gives quicker starts, smoother/lower RPM idles, more
power at low alt and better fuel economy at cruise. It has a stronger
spark that is more tolerant of ignition system degradation--a real world
reality. It uses cheap auto plugs that can be replaced at annual. It
saves weight. It doesn't rust, it doesn't require extra gears in the
engine to operate. And it does a lot of good things for that flame front
thing.
2. While reading this list for about 6 years, I compiled an
informal list of things to consider while constructing plane # 2 and many
concerned the ignition system. If anyone referred to the lml archives you
could find horror stories about mag gears grinding up engine internals, mag
corrosion from operation in the rain when the little drain hole was plugged,
unknown mistiming exceeding 10 degrees, and so on. Yet all the
experts want to quote Taylor and babble "Ada-speak" while ignoring these 'true
live stories".
3. And Brent: a) nothing has demonstrated lightning
protection, b) D-sub connectors are all over most homebuilts and work
fine, c) the crank sensor is only vulnerable to a bird strike if you fly without
a prop and spinner, d) everything is subject to accidental damage especially if
you have an exposed alt belt.
I salute Scott's willingness to experiment; I salute his willingness to
share results good and bad and take the crap. I wish I had his patience,
his grace. I really salute his push for data from the Ada crew with the
power point presentations who have yet to atch a chart with data to
support their assertions while demanding specifics from the rest of
us. Oh, and please no more PRISM praise until it has accumulated over 10,
000 flight hours like the rest of the EI systems out there.
Golly I feel better.
Paul Tackabury
pedigrees on file