In a message dated 12/25/2005 10:00:13 A.M. Central Standard Time,
mjrav@comcast.net writes:
Speed Demon,
Is there a practical way to establish more exact
timing?
I have one Electroair and one LSE system on my
IO360 with 9:1 compression.
When using an inductive timing light, indications
are very jumpy and seem unreliable.
I've noted that others have had this problem
also.
Stop using mag accessory case gear driven Hall effect devices and use the
LSE crankshaft sensor - Oh, wait.... doesn't the Rose system use a crank
sensor? Is the problem worse with the LSE or Electroair since LSE uses the
accessory case sensor? Have you done timing checks on each system
alone? Or, are you driving both systems with the same
sensor? Are the timing checks always done above 1800 RPM?
Things always seem fine at steady power for me. However, I don't have much
respect for the jumpy LSE display (all parameters, timing + or - 1
degree).
Is it possible to determine a "best " setting
based on other operating parameters?
As an example, I'm thinking of the "lean test" as
being used to analyze the relative performance of different
cylinders.
I know that overheating can be a symptom of too
much advance. Is there any useful
correlation?
The GAMI Lean test is extremely useful in determining the power differences
between cylinders by establishing the fuel flow to each at peak EGT. I use
the same Airflow Performance injector nozzles for each cylinder and
balanced air pressure to each, the max flow difference I see about .3 GPH max
spread, instrumentation accuracy notwithstanding. CHT differences (you did
mean cyl overheating, eh?) are often confusing because they can
frequently be altered by cooling air management and cylinder baffling as
well as power production.
Note: To bring the EGT on one cylinder closer to the other
three, I once switched from the .022 nozzle to a .023 nozzle in that cylinder
and the EGT dropped more below the average than it was above the average
before the swap. I changed back to the .022.
Fun stuff...
Scott Krueger
AKA Grayhawk
Lancair N92EX IO320 SB 89/96
Aurora, IL (KARR)
Merry
Christmas to all!