I agree and wonder how many of you spend much time above 5,000 and/or
on long cross country flights.
Takes a lot of fuel savings to pay for the control, EGT guage, and
installation. Leaning to peak rpm worked
for several years. My Cherokee 6 had an EGT and I ended up with the
same setting whether I leaned by
"ear" and tachometer or with the EGT. With the size engines in the
Ercoupe I doubt you are going to save
many engines or much fuel with a multi-probe EGT unless you are one
of the few who do a lot of high
altitude cross countries.
Dan C
On Feb 26, 2008, at 9:41 AM, John Cooper wrote:
If you have a mixture control and never touch it the result is the
same as
having the carb wired full rich or having the mixture control
completely
removed from the carburetor. (The legality of this latter option is
questionable).
The Stromberg mixture does function at full throttle, but the
effect is
reduced as the difference between the pressure in the throat and
ambient
pressure is much smaller.
The C-series Continentals do not have even enough fuel air
distribution to
support lean of peak operation.
The general rule of thumb is to not lean a Stromberg below 5000'
density
altitude. Above that lean for maximum RPM. Go slightly rich of the
peak if
you're climbing at full throttle. If there is no increase in RPM then
leaning is neither necessary nor beneficial.
Anything more than that is, IMHO, over analyzing the situation.
John Cooper
Skyport Services
518 797-3064
www.skyportservices.net
