Hi,
Thanks for the comments.
They don't and don't have to although some of your "factors" are "given" in
the chart makeup......it's the rate of flame front velocity change vs
piston speed/position by fuel that I'm really after. That will permit
programming the advance change rate. Purpose being that I believe most of
the losses that are really attributable to flame front/piston speed (RPM)
incompatibility (called VE change with RPM increase by many) can be
alleviated or at least partially counteracted by proper spark timing
advance relative to RPM. Nitro engine builders are finally doing this by
your method. I used the principle on an unblown alcohol engine for years by
running as much as 65 degrees of spark advance and therby increasing power
(and fuel use) about 15% at high RPM (7000) for that application.
The answer is "No I don't want the answer without doing the
homework".....this IS homework and having the data will get me closer to
having a dyno set up that might save me a day or two and maybe 20 gallons
of fuel! And a few pistons......
EGT was high (1500) on the engine last summer. Advanced the timing 2
degrees, killed the valves and annealed the heads.....go figure.
Thanks for all the info, I will use it.
Skip (still trying to advance to Auto Shop 102 without data)
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